Logging
Configuring cluster logging in OpenShift Container Platform 4.1
Abstract
Chapter 1. About cluster logging and OpenShift Container Platform
product-title} cluster logging aggregates all of the logs from your OpenShift Container Platform cluster, such as node system logs, application container logs, and so forth.
1.1. About cluster logging
OpenShift Container Platform cluster administrators can deploy cluster logging using a few CLI commands and the OpenShift Container Platform web console to install the Elasticsearch Operator and Cluster Logging Operator. When the operators are installed, create a Cluster Logging Custom Resource (CR) to schedule cluster logging pods and other resources necessary to support cluster logging. The operators are responsible for deploying, upgrading, and maintaining cluster logging.
You can configure cluster logging by modifying the Cluster Logging Custom Resource (CR), named instance
. The CR defines a complete cluster logging deployment that includes all the components of the logging stack to collect, store and visualize logs. The Cluster Logging Operator watches the ClusterLogging
Custom Resource and adjusts the logging deployment accordingly.
Administrators and application developers can view the logs of the projects for which they have view access.
1.1.1. About cluster logging components
The cluster logging components are based upon Elasticsearch, Fluentd, and Kibana (EFK). The collector, Fluentd, is deployed to each node in the OpenShift Container Platform cluster. It collects all node and container logs and writes them to Elasticsearch (ES). Kibana is the centralized, web UI where users and administrators can create rich visualizations and dashboards with the aggregated data.
There are currently 4 different types of cluster logging components:
- logStore - This is where the logs will be stored. The current implementation is Elasticsearch.
- collection - This is the component that collects logs from the node, formats them, and stores them in the logStore. The current implementation is Fluentd.
- visualization - This is the UI component used to view logs, graphs, charts, and so forth. The current implementation is Kibana.
- curation - This is the component that trims logs by age. The current implementation is Curator.
In this document, we may refer to logStore or Elasticsearch, visualization or Kibana, curation or Curator, collection or Fluentd, interchangeably, except where noted.
1.1.2. About Elasticsearch
OpenShift Container Platform uses Elasticsearch (ES) to organize the log data from Fluentd into datastores, or indices.
Elasticsearch subdivides each index into multiple pieces called shards, which it spreads across a set of Elasticsearch nodes in an Elasticsearch cluster. You can configure Elasticsearch to make copies of the shards, called replicas. Elasticsearch also spreads these replicas across the Elasticsearch nodes. The ClusterLogging Custom Resource allows you to specify the replication policy in the Custom Resource Definition (CRD) to provide data redundancy and resilience to failure.
The Cluster Logging Operator and companion Elasticsearch Operator ensure that each Elasticsearch node is deployed using a unique Deployment that includes its own storage volume. You can use a Cluster Logging Custom Resource (CR) to increase the number of Elasticsearch nodes. Refer to Elastic’s documentation for considerations involved in choosing storage and network location as directed below.
A highly-available Elasticsearch environment requires at least three Elasticsearch nodes, each on a different host.
For more information, see Elasticsearch (ES).
1.1.3. About Fluentd
OpenShift Container Platform uses Fluentd to collect data about your cluster.
Fluentd is deployed as a DaemonSet in OpenShift Container Platform that deploys pods to each OpenShift Container Platform node.
Fluentd uses journald
as the system log source. These are log messages from the operating system, the container runtime, and OpenShift Container Platform.
The container runtimes provide minimal information to identify the source of log messages: project, pod name, and container id. This is not sufficient to uniquely identify the source of the logs. If a pod with a given name and project is deleted before the log collector begins processing its logs, information from the API server, such as labels and annotations, is not be available. There might not be a way to distinguish the log messages from a similarly named pod and project or trace the logs to their source. This limitation means log collection and normalization is considered best effort.
The available container runtimes provide minimal information to identify the source of log messages and do not guarantee unique individual log messages or that these messages can be traced to their source.
For more information, see Fluentd.
1.1.4. About Kibana
OpenShift Container Platform uses Kibana to display the log data collected by Fluentd and indexed by Elasticsearch.
Kibana is a browser-based console interface to query, discover, and visualize your Elasticsearch data through histograms, line graphs, pie charts, heat maps, built-in geospatial support, and other visualizations.
For more information, see Kibana.
1.1.5. About Curator
The Elasticsearch Curator tool performs scheduled maintenance operations on a global and/or on a per-project basis. Curator performs actions daily based on its configuration. Only one Curator Pod is recommended per Elasticsearch cluster.
spec:
curation:
type: "curator"
resources:
curator:
schedule: "30 3 * * *" 1
- 1
- Specify the Curator schedule in the cron format.
For more information, see Curator.
1.1.6. About Event Router
The Event Router is a pod that forwards OpenShift Container Platform events to cluster logging. You must manually deploy Event Router.
The Event Router collects events and converts them into JSON format, which takes those events and pushes them to STDOUT
. Fluentd indexes the events to the .operations
index.
1.1.7. About the Cluster Logging Custom Resource Definition
The Cluster Logging Operator Custom Resource Definition (CRD) defines a complete cluster logging deployment that includes all the components of the logging stack to collect, store and visualize logs.
You should never have to modify this CRD. To make changes to your deployment, create and modify a specific Custom Resource (CR). Instructions for creating or modifying a CR are provided in this documentation as appropriate.
The following is an example of a typical Custom Resource for cluster logging.
Sample Cluster Logging CR
apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "instance" namespace: openshift-logging spec: managementState: "Managed" logStore: type: "elasticsearch" elasticsearch: nodeCount: 2 resources: limits: memory: 2Gi requests: cpu: 200m memory: 2Gi storage: storageClassName: "gp2" size: "200G" redundancyPolicy: "SingleRedundancy" visualization: type: "kibana" kibana: resources: limits: memory: 1Gi requests: cpu: 500m memory: 1Gi proxy: resources: limits: memory: 100Mi requests: cpu: 100m memory: 100Mi replicas: 2 curation: type: "curator" curator: resources: limits: memory: 200Mi requests: cpu: 200m memory: 200Mi schedule: "*/10 * * * *" collection: logs: type: "fluentd" fluentd: resources: limits: memory: 1Gi requests: cpu: 200m memory: 1Gi
Chapter 2. About deploying cluster logging
Before installing cluster logging into your cluster, review the following sections.
2.1. About deploying and configuring cluster logging
OpenShift Container Platform cluster logging is designed to be used with the default configuration, which is tuned for small to medium sized OpenShift Container Platform clusters.
The installation instructions that follow include a sample Cluster Logging Custom Resource (CR), which you can use to create a cluster logging instance and configure your cluster logging deployment.
If you want to use the default cluster logging install, you can use the sample CR directly.
If you want to customize your deployment, make changes to the sample CR as needed. The following describes the configurations you can make when installing your cluster logging instance or modify after installtion. See the Configuring sections for more information on working with each component, including modifications you can make outside of the Cluster Logging Custom Resource.
2.1.1. Configuring and Tuning Cluster Logging
You can configure your cluster logging environment by modifying the Cluster Logging Custom Resource deployed in the openshift-logging
project.
You can modify any of the following components upon install or after install:
- Memory and CPU
-
You can adjust both the CPU and memory limits for each component by modifying the
resources
block with valid memory and CPU values:
spec: logStore: elasticsearch: resources: limits: cpu: memory: requests: cpu: 1 memory: 16Gi type: "elasticsearch" collection: logs: fluentd: resources: limits: cpu: memory: requests: cpu: memory: type: "fluentd" visualization: kibana: resources: limits: cpu: memory: requests: cpu: memory: type: kibana curation: curator: resources: limits: memory: 200Mi requests: cpu: 200m memory: 200Mi type: "curator"
- Elasticsearch storage
-
You can configure a persistent storage class and size for the Elasticsearch cluster using the
storageClass
name
andsize
parameters. The Cluster Logging Operator creates aPersistentVolumeClaim
for each data node in the Elasticsearch cluster based on these parameters.
spec: logStore: type: "elasticsearch" elasticsearch: storage: storageClassName: "gp2" size: "200G"
This example specifies each data node in the cluster will be bound to a PersistentVolumeClaim
that requests "200G" of "gp2" storage. Each primary shard will be backed by a single replica.
Omitting the storage
block results in a deployment that includes ephemeral storage only.
spec: logStore: type: "elasticsearch" elasticsearch: storage: {}
- Elasticsearch replication policy
You can set the policy that defines how Elasticsearch shards are replicated across data nodes in the cluster:
-
FullRedundancy
. The shards for each index are fully replicated to every data node. -
MultipleRedundancy
. The shards for each index are spread over half of the data nodes. -
SingleRedundancy
. A single copy of each shard. Logs are always available and recoverable as long as at least two data nodes exist. -
ZeroRedundancy
. No copies of any shards. Logs may be unavailable (or lost) in the event a node is down or fails.
-
- Curator schedule
- You specify the schedule for Curator in the [cron format](https://en.wikipedia.org/wiki/Cron).
spec: curation: type: "curator" resources: curator: schedule: "30 3 * * *"
2.1.2. Sample modified Cluster Logging Custom Resource
The following is an example of a Cluster Logging Custom Resource modified using the options previously described.
Sample modified Cluster Logging Custom Resource
apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "instance" namespace: "openshift-logging" spec: managementState: "Managed" logStore: type: "elasticsearch" elasticsearch: nodeCount: 2 resources: limits: memory: 2Gi requests: cpu: 200m memory: 2Gi storage: {} redundancyPolicy: "SingleRedundancy" visualization: type: "kibana" kibana: resources: limits: memory: 1Gi requests: cpu: 500m memory: 1Gi replicas: 1 curation: type: "curator" curator: resources: limits: memory: 200Mi requests: cpu: 200m memory: 200Mi schedule: "*/5 * * * *" collection: logs: type: "fluentd" fluentd: resources: limits: memory: 1Gi requests: cpu: 200m memory: 1Gi
2.2. Storage considerations for cluster logging and OpenShift Container Platform
A persistent volume is required for each Elasticsearch deployment to have one data volume per data node. On OpenShift Container Platform this is achieved using Persistent Volume Claims.
The Elasticsearch Operator names the PVCs using the Elasticsearch resource name. Refer to Persistent Elasticsearch Storage for more details.
Fluentd ships any logs from systemd journal and /var/log/containers/ to Elasticsearch.
Therefore, consider how much data you need in advance and that you are aggregating application log data. Some Elasticsearch users have found that it is necessary to keep absolute storage consumption around 50% and below 70% at all times. This helps to avoid Elasticsearch becoming unresponsive during large merge operations.
By default, at 85% Elasticsearch stops allocating new data to the node, at 90% Elasticsearch attempts to relocate existing shards from that node to other nodes if possible. But if no nodes have free capacity below 85%, Elasticsearch effectively rejects creating new indices and becomes RED.
These low and high watermark values are Elasticsearch defaults in the current release. You can modify these values, but you also must apply any modifications to the alerts also. The alerts are based on these defaults.
2.3. Additional resources
For more information on installing operators,see Installing Operators from the OperatorHub.
Chapter 3. Deploying cluster logging
The process for deploying cluster Logging to OpenShift Container Platform involves:
- Review the installation options in About deploying cluster logging.
- Review the cluster logging storage considerations.
- Install the Cluster Logging subscription using the web console.
3.1. Installing the Cluster Logging and Elasticsearch Operators
You can use the OpenShift Container Platform console to install cluster logging, by deploying, the Cluster Logging and Elasticsearch Operators. The Cluster Logging Operator creates and manages the components of the logging stack. The Elasticsearch Operator creates and manages the Elasticsearch cluster used by cluster logging.
The OpenShift Container Platform cluster logging solution requires that you install both the Cluster Logging Operator and Elasticsearch Operator. There is no use case in OpenShift Container Platform for installing the operators individually. You must install the Elasticsearch Operator using the CLI following the directions below. You can install the Cluster Logging Operator using the web console or CLI.
Prerequisites
Ensure that you have the necessary persistent storage for Elasticsearch. Note that each Elasticsearch node requires its own storage volume.
Elasticsearch is a memory-intensive application. Each Elasticsearch node needs 16G of memory for both memory requests and limits. The initial set of OpenShift Container Platform nodes might not be large enough to support the Elasticsearch cluster. You must add additional nodes to the OpenShift Container Platform cluster to run with the recommended or higher memory. Each Elasticsearch node can operate with a lower memory setting though this is not recommended for production deployments.
You must install the Elasticsearch Operator using the CLI following the directions below. You can install the Cluster Logging Operator using the web console or CLI.
Procedure
Create Namespaces for the Elasticsearch Operator and Cluster Logging Operator.
NoteYou can also create the Namespaces in the web console using the Administration → Namespaces page. You must apply the
cluster-logging
andcluster-monitoring
labels listed in the sample YAML to the namespaces you create.Create a Namespace for the Elasticsearch Operator (for example,
eo-namespace.yaml
):apiVersion: v1 kind: Namespace metadata: name: openshift-operators-redhat 1 annotations: openshift.io/node-selector: "" labels: openshift.io/cluster-monitoring: "true" 2
- 1
- You must specify the
openshift-operators-redhat
namespace. To prevent possible conflicts with metrics, you should configure the Prometheus Cluster Monitoring stack to scrape metrics from theopenshift-operators-redhat
namespace and not theopenshift-operators
namespace. Theopenshift-operators
namespace can contain community operators, which are untrusted and could publish a metric with the same name as an OpenShift Container Platform metric, which would cause conflicts. - 2
- You must specify this label as shown to ensure that cluster monitoring scrapes the
openshift-operators-redhat
namespace.
Run the following command to create the namespace:
$ oc create -f <file-name>.yaml
For example:
$ oc create -f eo-namespace.yaml
Create a Namespace for the Cluster Logging Operator (for example,
clo-namespace.yaml
):apiVersion: v1 kind: Namespace metadata: name: openshift-logging 1 annotations: openshift.io/node-selector: "" 2 labels: 3 openshift.io/cluster-logging: "true" openshift.io/cluster-monitoring: "true"
Run the following command to create the namespace:
$ oc create -f <file-name>.yaml
For example:
$ oc create -f clo-namespace.yaml
Install the Elasticsearch Operator by creating the following objects:
Create an Operator Group object YAML file (for example,
eo-og.yaml
) for the Elasticsearch operator:apiVersion: operators.coreos.com/v1 kind: OperatorGroup metadata: name: openshift-operators-redhat namespace: openshift-operators-redhat 1 spec: {}
- 1
- You must specify the
openshift-operators-redhat
namespace.
Create an Operator Group object:
$ oc create -f eo-og.yaml
Create a CatalogSourceConfig object YAML file (for example,
eo-csc.yaml
) to enable the Elasticsearch Operator on the cluster.Example CatalogSourceConfig
apiVersion: "operators.coreos.com/v1" kind: "CatalogSourceConfig" metadata: name: "elasticsearch" namespace: "openshift-marketplace" spec: targetNamespace: "openshift-operators-redhat" 1 packages: "elasticsearch-operator" source: "redhat-operators"
- 1
- You must specify the
openshift-operators-redhat
namespace.
The Operator generates a CatalogSource from your CatalogSourceConfig in the namespace specified in
targetNamespace
.Create a CatalogSourceConfig object:
$ oc create -f eo-csc.yaml
Use the following command to get the
channel
value required for the next step.$ oc get packagemanifest elasticsearch-operator -n openshift-marketplace -o jsonpath='{.status.channels[].name}' preview
Create a Subscription object YAML file (for example,
eo-sub.yaml
) to subscribe a Namespace to an Operator.Example Subscription
apiVersion: operators.coreos.com/v1alpha1 kind: Subscription metadata: generateName: "elasticsearch-" namespace: "openshift-operators-redhat" 1 spec: channel: "preview" 2 installPlanApproval: "Automatic" source: "elasticsearch" sourceNamespace: "openshift-operators-redhat" 3 name: "elasticsearch-operator"
Create the Subscription object:
$ oc create -f eo-sub.yaml
Change to the
openshift-operators-redhat
project:$ oc project openshift-operators-redhat Now using project "openshift-operators-redhat"
Create a Role-based Access Control (RBAC) object file (for example,
eo-rbac.yaml
) to grant Prometheus permission to access theopenshift-operators-redhat
namespace:apiVersion: rbac.authorization.k8s.io/v1 kind: Role metadata: name: prometheus-k8s namespace: openshift-operators-redhat rules: - apiGroups: - "" resources: - services - endpoints - pods verbs: - get - list - watch --- apiVersion: rbac.authorization.k8s.io/v1 kind: RoleBinding metadata: name: prometheus-k8s namespace: openshift-operators-redhat roleRef: apiGroup: rbac.authorization.k8s.io kind: Role name: prometheus-k8s subjects: - kind: ServiceAccount name: prometheus-k8s namespace: openshift-operators-redhat
Create the RBAC object:
$ oc create -f eo-rbac.yaml
The Elasticsearch operator is installed to each project in the cluster.
Install the Cluster Logging Operator using the OpenShift Container Platform web console for best results:
- In the OpenShift Container Platform web console, click Catalog → OperatorHub.
- Choose Cluster Logging from the list of available Operators, and click Install.
- On the Create Operator Subscription page, under A specific namespace on the cluster select openshift-logging. Then, click Subscribe.
Verify the operator installations:
- Switch to the Catalog → Installed Operators page.
- Ensure that Cluster Logging is listed in the openshift-logging project with a Status of InstallSucceeded.
Ensure that Elasticsearch Operator is listed in the openshift-operator-redhat project with a Status of InstallSucceeded. The Elasticsearch Operator is copied to all other projects.
NoteDuring installation an operator might display a Failed status. If the operator then installs with an InstallSucceeded message, you can safely ignore the Failed message.
If either operator does not appear as installed, to troubleshoot further:
- Switch to the Catalog → Operator Management page and inspect the Operator Subscriptions and Install Plans tabs for any failure or errors under Status.
-
Switch to the Workloads → Pods page and check the logs in any Pods in the
openshift-logging
andopenshift-operators-redhat
projects that are reporting issues.
Create a cluster logging instance:
- Switch to the Administration → Custom Resource Definitions page.
- On the Custom Resource Definitions page, click ClusterLogging.
- On the Custom Resource Definition Overview page, select View Instances from the Actions menu.
On the Cluster Loggings page, click Create Cluster Logging.
You might have to refresh the page to load the data.
In the YAML, replace the code with the following:
NoteThis default cluster logging configuration should support a wide array of environments. Review the topics on tuning and configuring the cluster logging components for information on modifications you can make to your cluster logging cluster.
apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "instance" 1 namespace: "openshift-logging" spec: managementState: "Managed" 2 logStore: type: "elasticsearch" 3 elasticsearch: nodeCount: 3 4 storage: storageClassName: gp2 5 size: 200G redundancyPolicy: "SingleRedundancy" visualization: type: "kibana" 6 kibana: replicas: 1 curation: type: "curator" 7 curator: schedule: "30 3 * * *" collection: logs: type: "fluentd" 8 fluentd: {}
- 1
- The name of the CR. This must be
instance
. - 2
- The cluster logging management state. In most cases, if you change the default cluster logging defaults, you must set this to
Unmanaged
. However, an unmanaged deployment does not receive updates until the cluster logging is placed back into a managed state. For more information, see Changing cluster logging management state. - 3
- Settings for configuring Elasticsearch. Using the CR, you can configure shard replication policy and persistent storage. For more information, see Configuring Elasticsearch.
- 4
- Specify the number of Elasticsearch nodes. See the note that follows this list.
- 5
- Specify that each Elasticsearch node in the cluster is bound to a Persistent Volume Claim.
- 6
- Settings for configuring Kibana. Using the CR, you can scale Kibana for redundancy and configure the CPU and memory for your Kibana nodes. For more information, see Configuring Kibana.
- 7
- Settings for configuring Curator. Using the CR, you can set the Curator schedule. For more information, see Configuring Curator.
- 8
- Settings for configuring Fluentd. Using the CR, you can configure Fluentd CPU and memory limits. For more information, see Configuring Fluentd.
NoteThe maximum number of Elasticsearch master nodes is three. If you specify a
nodeCount
greater than3
, OpenShift Container Platform creates three Elasticsearch nodes that are Master-eligible nodes, with the master, client, and data roles. The additional Elasticsearch nodes are created as Data-only nodes, using client and data roles. Master nodes perform cluster-wide actions such as creating or deleting an index, shard allocation, and tracking nodes. Data nodes hold the shards and perform data-related operations such as CRUD, search, and aggregations. Data-related operations are I/O-, memory-, and CPU-intensive. It is important to monitor these resources and to add more Data nodes if the current nodes are overloaded.For example, if
nodeCount=4
, the following nodes are created:$ oc get deployment cluster-logging-operator 1/1 1 1 18h elasticsearch-cd-x6kdekli-1 0/1 1 0 6m54s elasticsearch-cdm-x6kdekli-1 1/1 1 1 18h elasticsearch-cdm-x6kdekli-2 0/1 1 0 6m49s elasticsearch-cdm-x6kdekli-3 0/1 1 0 6m44s
- Click Create. This creates the Cluster Logging Custom Resource and Elasticsearch Custom Resource, which you can edit to make changes to your cluster logging cluster.
Verify the install:
- Switch to the Workloads → Pods page.
Select the openshift-logging project.
You should see several pods for cluster logging, Elasticsearch, Fluentd, and Kibana similar to the following list:
- cluster-logging-operator-cb795f8dc-xkckc
- elasticsearch-cdm-b3nqzchd-1-5c6797-67kfz
- elasticsearch-cdm-b3nqzchd-2-6657f4-wtprv
- elasticsearch-cdm-b3nqzchd-3-588c65-clg7g
- fluentd-2c7dg
- fluentd-9z7kk
- fluentd-br7r2
- fluentd-fn2sb
- fluentd-pb2f8
- fluentd-zqgqx
- kibana-7fb4fd4cc9-bvt4p
3.2. Additional resources
For more information on installing operators,see Installing Operators from the OperatorHub.
Chapter 4. Viewing the Kibana interface
The cluster logging installation deploys the Kibana interface.
4.1. Launching the Kibana interface
The Kibana interface is a browser-based console to query, discover, and visualize your Elasticsearch data through histograms, line graphs, pie charts, heat maps, built-in geospatial support, and other visualizations.
Procedure
To launch the Kibana insteface:
- In the OpenShift Container Platform console, click Monitoring → Logging.
Log in using the same credentials you use to log into the OpenShift Container Platform console.
The Kibana interface launches. You can now:
- Search and browse your data using the Discover page.
- Chart and map your data using the Visualize page.
Create and view custom dashboards using the Dashboard page.
Use and configuration of the Kibana interface is beyond the scope of this documentation. For more information, on using the interface, see the Kibana documentation.
Chapter 5. Working with Event Router
The Event Router communicates with the OpenShift Container Platform and prints OpenShift Container Platform events to log of the pod where the event occurs.
If Cluster Logging is deployed, you can view the OpenShift Container Platform events in Kibana.
5.1. Deploying and Configuring the Event Router
Use the following steps to deploy Event Router into your cluster.
The following Template object creates the Service Account, ClusterRole, and ClusterRoleBinding required for the Event Router.
Prerequisites
- You need proper permissions to create service accounts and update cluster role bindings. For example, you can run the following template with a user that has the cluster-admin role.
Set
TRANSFORM_EVENTS=true
in order to process and store event router events in Elasticsearch.- Set cluster logging to the unmanaged state.
Enable the
TRANSFORM_EVENTS
feature.$ oc set env ds/fluentd TRANSFORM_EVENTS=true
Procedure
Create a template for the Event Router:
kind: Template apiVersion: v1 metadata: name: eventrouter-template annotations: description: "A pod forwarding kubernetes events to cluster logging stack." tags: "events,EFK,logging,cluster-logging" objects: - kind: ServiceAccount 1 apiVersion: v1 metadata: name: eventrouter namespace: ${NAMESPACE} - kind: ClusterRole 2 apiVersion: v1 metadata: name: event-reader rules: 3 - apiGroups: [""] resources: ["events"] verbs: ["get", "watch", "list"] - kind: ClusterRoleBinding 4 apiVersion: v1 metadata: name: event-reader-binding subjects: - kind: ServiceAccount name: eventrouter namespace: ${NAMESPACE} roleRef: kind: ClusterRole name: event-reader - kind: ConfigMap apiVersion: v1 metadata: name: eventrouter namespace: ${NAMESPACE} data: config.json: |- { "sink": "stdout" } - kind: Deployment apiVersion: apps/v1 metadata: name: eventrouter namespace: ${NAMESPACE} labels: component: eventrouter logging-infra: eventrouter provider: openshift spec: selector: matchLabels: component: eventrouter logging-infra: eventrouter provider: openshift replicas: 1 template: metadata: labels: component: eventrouter logging-infra: eventrouter provider: openshift name: eventrouter spec: serviceAccount: eventrouter containers: - name: kube-eventrouter image: ${IMAGE} imagePullPolicy: IfNotPresent resources: limits: memory: ${MEMORY} requests: cpu: ${CPU} memory: ${MEMORY} volumeMounts: - name: config-volume mountPath: /etc/eventrouter volumes: - name: config-volume configMap: name: eventrouter parameters: - name: IMAGE 5 displayName: Image value: "registry.redhat.io/openshift4/ose-logging-eventrouter:latest" - name: MEMORY 6 displayName: Memory value: "128Mi" - name: CPU 7 displayName: CPU value: "100m" - name: NAMESPACE 8 displayName: Namespace value: "openshift-logging"
- 1
- Creates a Service Account for the Event Router.
- 2
- Creates a cluster role to monitor for events in the cluster.
- 3
- Allows the
get
,watch
, andlist
permissions for theevents
resource. - 4
- Creates a ClusterRoleBinding to bind the ClusterRole to the ServiceAccount.
- 5
- Specify the image version for the Event Router.
- 6
- Specify the memory limit for the Event Router pods. Defaults to '128Mi'.
- 7
- Specify the minimum amount of CPU to allocate to the Event Router. Defaults to '100m'.
- 8
- Specify the namespace where eventrouter is deployed. Defaults to
openshift-logging
. The value must be the same as specified for the ServiceAccount and ClusterRoleBinding. The project indicates where in Kibana you can locate events:-
If the event router pod is deployed in a default project, such as
kube-*
andopenshift-*
, you can find the events under the .operation index. - If the event router pod is deployed in other projects, you can find the event under the index using the project namespace.
-
If the event router pod is deployed in a default project, such as
Use the following command to process and apply the template:
$ oc process -f <templatefile> | oc apply -f -
For example:
$ oc process -f eventrouter.yaml | oc apply -f - serviceaccount/logging-eventrouter created clusterrole.authorization.openshift.io/event-reader created clusterrolebinding.authorization.openshift.io/event-reader-binding created configmap/logging-eventrouter created deployment.apps/logging-eventrouter created
Validate that the Event Router installed:
$ oc get pods --selector component=eventrouter -o name pod/logging-eventrouter-d649f97c8-qvv8r
$ oc logs logging-eventrouter-d649f97c8-qvv8r {"verb":"ADDED","event":{"metadata":{"name":"elasticsearch-operator.v0.0.1.158f402e25397146","namespace":"openshift-operators","selfLink":"/api/v1/namespaces/openshift-operators/events/elasticsearch-operator.v0.0.1.158f402e25397146","uid":"37b7ff11-4f1a-11e9-a7ad-0271b2ca69f0","resourceVersion":"523264","creationTimestamp":"2019-03-25T16:22:43Z"},"involvedObject":{"kind":"ClusterServiceVersion","namespace":"openshift-operators","name":"elasticsearch-operator.v0.0.1","uid":"27b2ca6d-4f1a-11e9-8fba-0ea949ad61f6","apiVersion":"operators.coreos.com/v1alpha1","resourceVersion":"523096"},"reason":"InstallSucceeded","message":"waiting for install components to report healthy","source":{"component":"operator-lifecycle-manager"},"firstTimestamp":"2019-03-25T16:22:43Z","lastTimestamp":"2019-03-25T16:22:43Z","count":1,"type":"Normal"}}
Chapter 6. Configuring your cluster logging deployment
6.1. About configuring cluster logging
After installing cluster logging into your cluster, you can make the following configurations.
You must set cluster logging to Unmanaged state before performing these configurations, unless otherwise noted. For more information, see Changing the cluster logging management state.
6.1.1. About deploying and configuring cluster logging
OpenShift Container Platform cluster logging is designed to be used with the default configuration, which is tuned for small to medium sized OpenShift Container Platform clusters.
The installation instructions that follow include a sample Cluster Logging Custom Resource (CR), which you can use to create a cluster logging instance and configure your cluster logging deployment.
If you want to use the default cluster logging install, you can use the sample CR directly.
If you want to customize your deployment, make changes to the sample CR as needed. The following describes the configurations you can make when installing your cluster logging instance or modify after installtion. See the Configuring sections for more information on working with each component, including modifications you can make outside of the Cluster Logging Custom Resource.
6.1.1.1. Configuring and Tuning Cluster Logging
You can configure your cluster logging environment by modifying the Cluster Logging Custom Resource deployed in the openshift-logging
project.
You can modify any of the following components upon install or after install:
- Memory and CPU
-
You can adjust both the CPU and memory limits for each component by modifying the
resources
block with valid memory and CPU values:
spec: logStore: elasticsearch: resources: limits: cpu: memory: requests: cpu: 1 memory: 16Gi type: "elasticsearch" collection: logs: fluentd: resources: limits: cpu: memory: requests: cpu: memory: type: "fluentd" visualization: kibana: resources: limits: cpu: memory: requests: cpu: memory: type: kibana curation: curator: resources: limits: memory: 200Mi requests: cpu: 200m memory: 200Mi type: "curator"
- Elasticsearch storage
-
You can configure a persistent storage class and size for the Elasticsearch cluster using the
storageClass
name
andsize
parameters. The Cluster Logging Operator creates aPersistentVolumeClaim
for each data node in the Elasticsearch cluster based on these parameters.
spec: logStore: type: "elasticsearch" elasticsearch: storage: storageClassName: "gp2" size: "200G"
This example specifies each data node in the cluster will be bound to a PersistentVolumeClaim
that requests "200G" of "gp2" storage. Each primary shard will be backed by a single replica.
Omitting the storage
block results in a deployment that includes ephemeral storage only.
spec: logStore: type: "elasticsearch" elasticsearch: storage: {}
- Elasticsearch replication policy
You can set the policy that defines how Elasticsearch shards are replicated across data nodes in the cluster:
-
FullRedundancy
. The shards for each index are fully replicated to every data node. -
MultipleRedundancy
. The shards for each index are spread over half of the data nodes. -
SingleRedundancy
. A single copy of each shard. Logs are always available and recoverable as long as at least two data nodes exist. -
ZeroRedundancy
. No copies of any shards. Logs may be unavailable (or lost) in the event a node is down or fails.
-
- Curator schedule
- You specify the schedule for Curator in the [cron format](https://en.wikipedia.org/wiki/Cron).
spec: curation: type: "curator" resources: curator: schedule: "30 3 * * *"
6.1.1.2. Sample modified Cluster Logging Custom Resource
The following is an example of a Cluster Logging Custom Resource modified using the options previously described.
Sample modified Cluster Logging Custom Resource
apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "instance" namespace: "openshift-logging" spec: managementState: "Managed" logStore: type: "elasticsearch" elasticsearch: nodeCount: 2 resources: limits: memory: 2Gi requests: cpu: 200m memory: 2Gi storage: {} redundancyPolicy: "SingleRedundancy" visualization: type: "kibana" kibana: resources: limits: memory: 1Gi requests: cpu: 500m memory: 1Gi replicas: 1 curation: type: "curator" curator: resources: limits: memory: 200Mi requests: cpu: 200m memory: 200Mi schedule: "*/5 * * * *" collection: logs: type: "fluentd" fluentd: resources: limits: memory: 1Gi requests: cpu: 200m memory: 1Gi
6.1.2. Moving the cluster logging resources
You can configure the Cluster Logging Operator to deploy the pods for any or all of the Cluster Logging components, Elasticsearch, Kibana, and Curator to different nodes. You cannot move the Cluster Logging Operator pod from its installed location.
For example, you can move the Elasticsearch pods to a separate node because of high CPU, memory, and disk requirements.
You should set your MachineSet to use at least 6 replicas.
Prerequisites
- Cluster logging and Elasticsearch must be installed. These features are not installed by default.
Procedure
Edit the Cluster Logging Custom Resource in the
openshift-logging
project:$ oc edit ClusterLogging instance
apiVersion: logging.openshift.io/v1 kind: ClusterLogging .... spec: collection: logs: fluentd: resources: null rsyslog: resources: null type: fluentd curation: curator: nodeSelector: 1 node-role.kubernetes.io/infra: '' resources: null schedule: 30 3 * * * type: curator logStore: elasticsearch: nodeCount: 3 nodeSelector: 2 node-role.kubernetes.io/infra: '' redundancyPolicy: SingleRedundancy resources: limits: cpu: 500m memory: 16Gi requests: cpu: 500m memory: 16Gi storage: {} type: elasticsearch managementState: Managed visualization: kibana: nodeSelector: 3 node-role.kubernetes.io/infra: '' 4 proxy: resources: null replicas: 1 resources: null type: kibana ....
6.2. Changing cluster logging management state
In order to modify certain components managed by the Cluster Logging Operator or the Elasticsearch Operator, you must set the operator to the unmanaged state.
In unmanaged state, the operators do not respond to changes in the CRs. The administrator assumes full control of individual component configurations and upgrades when in unmanaged state.
In managed state, the Cluster Logging Operator (CLO) responds to changes in the Cluster Logging Custom Resource (CR) and attempts to update the cluster to match the CR.
The OpenShift Container Platform documentation indicates in a prerequisite step when you must set the cluster to Unmanaged.
If you set the Elasticsearch Operator (EO) to unmanaged and leave the Cluster Logging Operator (CLO) as managed, the CLO will revert changes you make to the EO, as the EO is managed by the CLO.
6.2.1. Changing the cluster logging management state
You must set the operator to the unmanaged state in order to modify the components managed by the Cluster Logging Operator:
- the Curator CronJob,
- the Elasticsearch CR,
- the Kibana Deployment,
- the log collector DaemonSet.
If you make changes to these components in managed state, the Cluster Logging Operator reverts those changes.
An unmanaged cluster logging environment does not receive updates until you return the Cluster Logging Operator to Managed state.
Prerequisites
- The Cluster Logging Operator must be installed.
Procedure
Edit the Cluster Logging Custom Resource (CR) in the
openshift-logging
project:$ oc edit ClusterLogging instance
$ oc edit ClusterLogging instance apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "instance" .... spec: managementState: "Managed" 1
- 1
- Specify the management state as
Managed
orUnmanaged
.
6.2.2. Changing the Elasticsearch management state
You must set the operator to the unmanaged state in order to modify the Elasticsearch deployment files, which are managed by the Elasticsearch Operator.
If you make changes to these components in managed state, the Elsticsearch Operator reverts those changes.
An unmanaged Elasticsearch cluster does not receive updates until you return the Elasticsearch Operator to Managed state.
Prerequisite
- The Elasticsearch Operator must be installed.
Have the name of the Elasticsearch CR, in the
openshift-logging
project:$ oc get -n openshift-logging Elasticsearch NAME AGE elasticsearch 28h
Procedure
Edit the Elasticsearch Custom Resource (CR) in the openshift-logging
project:
$ oc edit Elasticsearch elasticsearch
apiVersion: logging.openshift.io/v1
kind: Elasticsearch
metadata:
name: elasticsearch
....
spec:
managementState: "Managed" 1
- 1
- Specify the management state as
Managed
orUnmanaged
.
If you set the Elasticsearch Operator (EO) to unmanaged and leave the Cluster Logging Operator (CLO) as managed, the CLO will revert changes you make to the EO, as the EO is managed by the CLO.
6.3. Configuring cluster logging
Cluster logging is configurable using a Cluster Logging Custom Resource (CR) deployed in the openshift-logging
project.
The Cluster Logging Operator watches for changes to Cluster Logging CRs, creates any missing logging components, and adjusts the logging deployment accordingly.
The Cluster Logging CR is based on the Cluster Logging Custom Resource Definition (CRD), which defines a complete cluster logging deployment and includes all the components of the logging stack to collect, store and visualize logs.
Sample Cluster Logging Custom Resource (CR)
apiVersion: logging.openshift.io/v1 kind: ClusterLogging metadata: creationTimestamp: '2019-03-20T18:07:02Z' generation: 1 name: instance namespace: openshift-logging spec: collection: logs: fluentd: resources: null rsyslog: resources: null type: fluentd curation: curator: resources: null schedule: 30 3 * * * type: curator logStore: elasticsearch: nodeCount: 3 redundancyPolicy: SingleRedundancy resources: limits: cpu: memory: requests: cpu: memory: storage: {} type: elasticsearch managementState: Managed visualization: kibana: proxy: resources: null replicas: 1 resources: null type: kibana
You can configure the following for cluster logging:
- You can place cluster logging into an unmanaged state that allows an administrator to assume full control of individual component configurations and upgrades.
-
You can overwrite the image for each cluster logging component by modifying the appropriate environment variable in the
cluster-logging-operator
Deployment. - You can specify specific nodes for the logging components using node selectors.
6.3.1. Understanding the cluster logging component images
There are several components in cluster logging, each one implemented with one or more images. Each image is specified by an environment variable defined in the cluster-logging-operator deployment in the openshift-logging project and should not be changed.
You can view the images by running the following command:
oc -n openshift-logging set env deployment/cluster-logging-operator --list | grep _IMAGE ELASTICSEARCH_IMAGE=registry.redhat.io/openshift4/ose-logging-elasticsearch5:v4.1 1 FLUENTD_IMAGE=registry.redhat.io/openshift4/ose-logging-fluentd:v4.1 2 KIBANA_IMAGE=registry.redhat.io/openshift4/ose-logging-kibana5:v4.1 3 CURATOR_IMAGE=registry.redhat.io/openshift4/ose-logging-curator5:v4.1 4 OAUTH_PROXY_IMAGE=registry.redhat.io/openshift4/ose-oauth-proxy:v4.1 5
The values might be different depending on your environment.
6.4. Configuring Elasticsearch to store and organize log data
OpenShift Container Platform uses Elasticsearch (ES) to store and organize the log data.
You can configure your Elasticsearch deployment to:
- configure storage for your Elasticsearch cluster;
- define how shards are replicated across data nodes in the cluster, from full replication to no replication;
- configure external access to Elasticsearch data.
Scaling down Elasticsearch nodes is not supported. When scaling down, Elasticsearch pods can be accidentally deleted, possibly resulting in shards not being allocated and replica shards being lost.
Elasticsearch is a memory-intensive application. Each Elasticsearch node needs 16G of memory for both memory requests and CPU limits, unless you specify otherwise in the ClusterLogging Custom Resource. The initial set of OpenShift Container Platform nodes might not be large enough to support the Elasticsearch cluster. You must add additional nodes to the OpenShift Container Platform cluster to run with the recommended or higher memory.
Each Elasticsearch node can operate with a lower memory setting though this is not recommended for production deployments.
If you set the Elasticsearch Operator (EO) to unmanaged and leave the Cluster Logging Operator (CLO) as managed, the CLO will revert changes you make to the EO, as the EO is managed by the CLO.
6.4.1. Configuring Elasticsearch CPU and memory limits
Each component specification allows for adjustments to both the CPU and memory limits. You should not have to manually adjust these values as the Elasticsearch Operator sets values sufficient for your environment.
Each Elasticsearch node can operate with a lower memory setting though this is not recommended for production deployments. For production use, you should have no less than the default 16Gi allocated to each Pod. Preferably you should allocate as much as possible, up to 64Gi per Pod.
Prerequisites
- Cluster logging and Elasticsearch must be installed.
Procedure
Edit the Cluster Logging Custom Resource (CR) in the
openshift-logging
project:$ oc edit ClusterLogging instance
apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "instance" .... spec: logStore: type: "elasticsearch" elasticsearch: resources: 1 limits: memory: "16Gi" requests: cpu: "1" memory: "16Gi"
- 1
- Specify the CPU and memory limits as needed. If you leave these values blank, the Elasticsearch Operator sets default values that should be sufficient for most deployments.
6.4.2. Configuring Elasticsearch replication policy
You can define how Elasticsearch shards are replicated across data nodes in the cluster:
Prerequisites
- Cluster logging and Elasticsearch must be installed.
Procedure
Edit the Cluster Logging Custom Resource (CR) in the
openshift-logging
project:oc edit clusterlogging instance
apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "instance" .... spec: logStore: type: "elasticsearch" elasticsearch: redundancyPolicy: "SingleRedundancy" 1
- 1
- Specify a redundancy policy for the shards. The change is applied upon saving the changes.
- FullRedundancy. Elasticsearch fully replicates the primary shards for each index to every data node. This provides the highest safety, but at the cost of the highest amount of disk required and the poorest performance.
- MultipleRedundancy. Elasticsearch fully replicates the primary shards for each index to half of the data nodes. This provides a good tradeoff between safety and performance.
- SingleRedundancy. Elasticsearch makes one copy of the primary shards for each index. Logs are always available and recoverable as long as at least two data nodes exist. Better performance than MultipleRedundancy, when using 5 or more nodes. You cannot apply this policy on deployments of single Elasticsearch node.
- ZeroRedundancy. Elasticsearch does not make copies of the primary shards. Logs might be unavailable or lost in the event a node is down or fails. Use this mode when you are more concerned with performance than safety, or have implemented your own disk/PVC backup/restore strategy.
6.4.3. Configuring Elasticsearch storage
Elasticsearch requires persistent storage. The faster the storage, the faster the Elasticsearch performance is.
Using NFS storage as a volume or a persistent volume (or via NAS such as Gluster) is not supported for Elasticsearch storage, as Lucene relies on file system behavior that NFS does not supply. Data corruption and other problems can occur.
Prerequisites
- Cluster logging and Elasticsearch must be installed.
Procedure
Edit the Cluster Logging CR to specify that each data node in the cluster is bound to a Persistent Volume Claim.
apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "instance" .... spec: logStore: type: "elasticsearch" elasticsearch: nodeCount: 3 storage: storageClassName: "gp2" size: "200G"
This example specifies each data node in the cluster is bound to a Persistent Volume Claim that requests "200G" of AWS General Purpose SSD (gp2) storage.
6.4.4. Configuring Elasticsearch for emptyDir storage
You can use emptyDir with Elasticsearch, which creates an ephemeral deployment in which all of a pod’s data is lost upon restart.
When using emptyDir, if Elasticsearch is restarted or redeployed, you will lose data.
Prerequisites
- Cluster logging and Elasticsearch must be installed.
Procedure
Edit the Cluster Logging CR to specify emptyDir:
spec: logStore: type: "elasticsearch" elasticsearch: nodeCount: 3 storage: {}
6.4.5. Exposing Elasticsearch as a route
By default, Elasticsearch deployed with cluster logging is not accessible from outside the logging cluster. You can enable a route with re-encryption termination for external access to Elasticsearch for those tools that access its data.
Externally, you can access Elasticsearch by creating a reencrypt route, your OpenShift Container Platform token and the installed Elasticsearch CA certificate. Then, access an Elasticsearch node with a cURL request that contains:
-
The
Authorization: Bearer ${token}
- The Elasticsearch reencrypt route and an Elasticsearch API request.
Internally, you can access Elastiscearch using the Elasticsearch cluster IP:
$ oc get service elasticsearch -o jsonpath={.spec.clusterIP} -n openshift-logging 172.30.183.229 oc get service elasticsearch NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE elasticsearch ClusterIP 172.30.183.229 <none> 9200/TCP 22h $ oc exec elasticsearch-cdm-oplnhinv-1-5746475887-fj2f8 -- curl -tlsv1.2 --insecure -H "Authorization: Bearer ${token}" "https://172.30.183.229:9200/_cat/health" % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent Left Speed 100 29 100 29 0 0 108 0 --:--:-- --:--:-- --:--:-- 108
Prerequisites
- Cluster logging and Elasticsearch must be installed.
- You must have access to the project in order to be able to access to the logs. For example:
Procedure
To expose Elasticsearch externally:
Change to the
openshift-logging
project:$ oc project openshift-logging
Extract the CA certificate from Elasticsearch and write to the admin-ca file:
$ oc extract secret/elasticsearch --to=. --keys=admin-ca admin-ca
Create the route for the Elasticsearch service as a YAML file:
Create a YAML file with the following:
apiVersion: route.openshift.io/v1 kind: Route metadata: name: elasticsearch namespace: openshift-logging spec: host: to: kind: Service name: elasticsearch tls: termination: reencrypt destinationCACertificate: | 1
- 1
- Add the Elasticsearch CA certifcate or use the command in the next step. You do not have to set the
spec.tls.key
,spec.tls.certificate
, andspec.tls.caCertificate
parameters required by some reencrypt routes.
Add the Elasticsearch CA certificate to the route YAML you created:
cat ./admin-ca | sed -e "s/^/ /" >> <file-name>.yaml
Create the route:
$ oc create -f <file-name>.yaml route.route.openshift.io/elasticsearch created
Check that the Elasticsearch service is exposed:
Get the token of this ServiceAccount to be used in the request:
$ token=$(oc whoami -t)
Set the elasticsearch route you created as an environment variable.
$ routeES=`oc get route elasticsearch -o jsonpath={.spec.host}`
To verify the route was successfully created, run the following command that accesses Elasticsearch through the exposed route:
curl -tlsv1.2 --insecure -H "Authorization: Bearer ${token}" "https://${routeES}/.operations.*/_search?size=1" | jq
The response appears similar to the following:
% Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent Left Speed 100 944 100 944 0 0 62 0 0:00:15 0:00:15 --:--:-- 204 { "took": 441, "timed_out": false, "_shards": { "total": 3, "successful": 3, "skipped": 0, "failed": 0 }, "hits": { "total": 89157, "max_score": 1, "hits": [ { "_index": ".operations.2019.03.15", "_type": "com.example.viaq.common", "_id": "ODdiNWIyYzAtMjg5Ni0TAtNWE3MDY1MjMzNTc3", "_score": 1, "_source": { "_SOURCE_MONOTONIC_TIMESTAMP": "673396", "systemd": { "t": { "BOOT_ID": "246c34ee9cdeecb41a608e94", "MACHINE_ID": "e904a0bb5efd3e36badee0c", "TRANSPORT": "kernel" }, "u": { "SYSLOG_FACILITY": "0", "SYSLOG_IDENTIFIER": "kernel" } }, "level": "info", "message": "acpiphp: Slot [30] registered", "hostname": "localhost.localdomain", "pipeline_metadata": { "collector": { "ipaddr4": "10.128.2.12", "ipaddr6": "fe80::xx:xxxx:fe4c:5b09", "inputname": "fluent-plugin-systemd", "name": "fluentd", "received_at": "2019-03-15T20:25:06.273017+00:00", "version": "1.3.2 1.6.0" } }, "@timestamp": "2019-03-15T20:00:13.808226+00:00", "viaq_msg_id": "ODdiNWIyYzAtMYTAtNWE3MDY1MjMzNTc3" } } ] } }
6.4.6. About Elasticsearch alerting rules
You can view these alerting rules in Prometheus.
Alert | Description | Severity |
---|---|---|
ElasticsearchClusterNotHealthy | Cluster health status has been RED for at least 2m. Cluster does not accept writes, shards may be missing or master node hasn’t been elected yet. | critical |
ElasticsearchClusterNotHealthy | Cluster health status has been YELLOW for at least 20m. Some shard replicas are not allocated. | warning |
ElasticsearchBulkRequestsRejectionJumps | High Bulk Rejection Ratio at node in cluster. This node may not be keeping up with the indexing speed. | warning |
ElasticsearchNodeDiskWatermarkReached | Disk Low Watermark Reached at node in cluster. Shards can not be allocated to this node anymore. You should consider adding more disk to the node. | alert |
ElasticsearchNodeDiskWatermarkReached | Disk High Watermark Reached at node in cluster. Some shards will be re-allocated to different nodes if possible. Make sure more disk space is added to the node or drop old indices allocated to this node. | high |
ElasticsearchJVMHeapUseHigh | JVM Heap usage on the node in cluster is <value> | alert |
AggregatedLoggingSystemCPUHigh | System CPU usage on the node in cluster is <value> | alert |
ElasticsearchProcessCPUHigh | ES process CPU usage on the node in cluster is <value> | alert |
6.5. Configuring Kibana
OpenShift Container Platform uses Kibana to display the log data collected by Fluentd and indexed by Elasticsearch.
You can scale Kibana for redundancy and configure the CPU and memory for your Kibana nodes.
You must set cluster logging to Unmanaged state before performing these configurations, unless otherwise noted. For more information, see Changing the cluster logging management state.
6.5.1. Configure Kibana CPU and memory limits
Each component specification allows for adjustments to both the CPU and memory limits.
Procedure
Edit the Cluster Logging Custom Resource (CR) in the
openshift-logging
project:$ oc edit ClusterLogging instance
apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "instance" .... spec: visualization: type: "kibana" kibana: replicas: resources: 1 limits: memory: 1Gi requests: cpu: 500m memory: 1Gi proxy: 2 resources: limits: memory: 100Mi requests: cpu: 100m memory: 100Mi
6.5.2. Scaling Kibana for redundancy
You can scale the Kibana deployment for redundancy.
..Procedure
Edit the Cluster Logging Custom Resource (CR) in the
openshift-logging
project:$ oc edit ClusterLogging instance
$ oc edit ClusterLogging instance apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "instance" .... spec: visualization: type: "kibana" kibana: replicas: 1 1
- 1
- Specify the number of Kibana nodes.
6.5.3. Installing the Kibana Visualize tool
Kibana’s Visualize tab enables you to create visualizations and dashboards for monitoring container logs, allowing administrator users (cluster-admin
or cluster-reader
) to view logs by deployment, namespace, pod, and container.
Procedure
To load dashboards and other Kibana UI objects:
If necessary, get the Kibana route, which is created by default upon installation of the Cluster Logging Operator:
$ oc get routes -n openshift-logging NAMESPACE NAME HOST/PORT PATH SERVICES PORT TERMINATION WILDCARD openshift-logging kibana kibana-openshift-logging.apps.openshift.com kibana <all> reencrypt/Redirect None
Get the name of your Elasticsearch pods.
$ oc get pods -l component=elasticsearch NAME READY STATUS RESTARTS AGE elasticsearch-cdm-5ceex6ts-1-dcd6c4c7c-jpw6k 2/2 Running 0 22h elasticsearch-cdm-5ceex6ts-2-f799564cb-l9mj7 2/2 Running 0 22h elasticsearch-cdm-5ceex6ts-3-585968dc68-k7kjr 2/2 Running 0 22h
Create the necessary per-user configuration that this procedure requires:
Log in to the Kibana dashboard as the user you want to add the dashboards to.
https://kibana-openshift-logging.apps.openshift.com 1
- 1
- Where the URL is Kibana route.
- If the Authorize Access page appears, select all permissions and click Allow selected permissions.
- Log out of the Kibana dashboard.
Run the following command from the project where the pod is located using the name of any of your Elastiscearch pods:
$ oc exec <es-pod> -- es_load_kibana_ui_objects <user-name>
For example:
$ oc exec elasticsearch-cdm-5ceex6ts-1-dcd6c4c7c-jpw6k -- es_load_kibana_ui_objects <user-name>
6.6. Curation of Elasticsearch Data
The Elasticsearch Curator tool performs scheduled maintenance operations on a global and/or on a per-project basis. Curator performs actions daily based on its configuration.
The Cluster Logging Operator installs Curator and its configuration. You can configure the Curator cron schedule using the Cluster Logging Custom Resource and further configuration options can be found in the Curator ConfigMap, curator
in the openshift-logging
project, which incorporates the Curator configuration file, curator5.yaml and an OpenShift Container Platform custom configuration file, config.yaml.
OpenShift Container Platform uses the config.yaml internally to generate the Curator action
file.
Optionally, you can use the action
file, directly. Editing this file allows you to use any action that Curator has available to it to be run periodically. However, this is only recommended for advanced users as modifying the file can be destructive to the cluster and can cause removal of required indices/settings from Elasticsearch. Most users only must modify the Curator configuration map and never edit the action
file.
6.6.1. Configuring the Curator schedule
You can specify the schedule for Curator using the cluster logging Custom Resource created by the cluster logging installation.
Prerequisites
- Cluster logging and Elasticsearch must be installed.
Procedure
To configure the Curator schedule:
Edit the Cluster Logging Custom Resource in the
openshift-logging
project:$ oc edit clusterlogging instance
apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "instance" ... curation: curator: schedule: 30 3 * * * 1 type: curator
- 1
- Specify the schedule for Curator in cron format.
NoteThe time zone is set based on the host node where the Curator pod runs.
6.6.2. Configuring Curator index deletion
You can configure Curator to delete Elasticsearch data based on retention settings. You can configure per-project and global settings. Global settings apply to any project not specified. Per-project settings override global settings.
Prerequisite
- Cluster logging must be installed.
Procedure
To delete indices:
Edit the OpenShift Container Platform custom Curator configuration file:
$ oc edit configmap/curator
Set the following parameters as needed:
config.yaml: | project_name: action unit:value
The available parameters are:
Table 6.1. Project options Variable Name Description project_name
The actual name of a project, such as myapp-devel. For OpenShift Container Platform operations logs, use the name
.operations
as the project name.action
The action to take, currently only
delete
is allowed.unit
The period to use for deletion,
days
,weeks
, ormonths
.value
The number of units.
Table 6.2. Filter options Variable Name Description .defaults
Use
.defaults
as theproject_name
to set the defaults for projects that are not specified..regex
The list of regular expressions that match project names.
pattern
The valid and properly escaped regular expression pattern enclosed by single quotation marks.
For example, to configure Curator to:
-
Delete indices in the myapp-dev project older than
1 day
-
Delete indices in the myapp-qe project older than
1 week
-
Delete operations logs older than
8 weeks
-
Delete all other projects indices after they are
31 days
old -
Delete indices older than 1 day that are matched by the
^project\..+\-dev.*$
regex -
Delete indices older than 2 days that are matched by the
^project\..+\-test.*$
regex
Use:
config.yaml: | .defaults: delete: days: 31 .operations: delete: weeks: 8 myapp-dev: delete: days: 1 myapp-qe: delete: weeks: 1 .regex: - pattern: '^project\..+\-dev\..*$' delete: days: 1 - pattern: '^project\..+\-test\..*$' delete: days: 2
When you use months
as the $UNIT
for an operation, Curator starts counting at the first day of the current month, not the current day of the current month. For example, if today is April 15, and you want to delete indices that are 2 months older than today (delete: months: 2), Curator does not delete indices that are dated older than February 15; it deletes indices older than February 1. That is, it goes back to the first day of the current month, then goes back two whole months from that date. If you want to be exact with Curator, it is best to use days (for example, delete: days: 30
).
6.6.3. Troubleshooting Curator
You can use information in this section for debugging Curator. For example, if curator is in failed state, but the log messages do not provide a reason, you could increase the log level and trigger a new job, instead of waiting for another scheduled run of the cron job.
Prerequisites
Cluster logging and Elasticsearch must be installed.
Procedure
Enable the Curator debug log and trigger next Curator iteration manually
Enable debug log of Curator:
$ oc set env cronjob/curator CURATOR_LOG_LEVEL=DEBUG CURATOR_SCRIPT_LOG_LEVEL=DEBUG
Specify the log level:
- CRITICAL. Curator displays only critical messages.
- ERROR. Curator displays only error and critical messages.
- WARNING. Curator displays only error, warning, and critical messages.
- INFO. Curator displays only informational, error, warning, and critical messages.
DEBUG. Curator displays only debug messages, in addition to all of the above.
The default value is INFO.
Cluster logging uses the OpenShift Container Platform custom environment variable CURATOR_SCRIPT_LOG_LEVEL
in OpenShift Container Platform wrapper scripts (run.sh
and convert.py
). The environment variable takes the same values as CURATOR_LOG_LEVEL
for script debugging, as needed.
Trigger next curator iteration:
$ oc create job --from=cronjob/curator <job_name>
Use the following commands to control the CronJob:
Suspend a CronJob:
$ oc patch cronjob curator -p '{"spec":{"suspend":true}}'
Resume a CronJob:
$ oc patch cronjob curator -p '{"spec":{"suspend":false}}'
Change a CronJob schedule:
$ oc patch cronjob curator -p '{"spec":{"schedule":"0 0 * * *"}}' 1
- 1
- The
schedule
option accepts schedules in cron format.
6.6.4. Configuring Curator in scripted deployments
Use the information in this section if you must configure Curator in scripted deployments.
Prerequisites
- Cluster logging and Elasticsearch must be installed.
- Set cluster logging to the unmanaged state.
Procedure
Use the following snippets to configure Curator in your scripts:
For scripted deployments
Create and modify the configuration:
Copy the Curator configuration file and the OpenShift Container Platform custom configuration file from the Curator configuration map and create separate files for each:
$ oc extract configmap/curator --keys=curator5.yaml,config.yaml --to=/my/config
- Edit the /my/config/curator5.yaml and /my/config/config.yaml files.
Delete the existing Curator config map and add the edited YAML files to a new Curator config map.
$ oc delete configmap curator ; sleep 1 $ oc create configmap curator \ --from-file=curator5.yaml=/my/config/curator5.yaml \ --from-file=config.yaml=/my/config/config.yaml \ ; sleep 1
The next iteration will use this configuration.
If you are using the action file:
Create and modify the configuration:
Copy the Curator configuration file and the action file from the Curator configuration map and create separate files for each:
$ oc extract configmap/curator --keys=curator5.yaml,actions.yaml --to=/my/config
- Edit the /my/config/curator5.yaml and /my/config/actions.yaml files.
Delete the existing Curator config map and add the edited YAML files to a new Curator config map.
$ oc delete configmap curator ; sleep 1 $ oc create configmap curator \ --from-file=curator5.yaml=/my/config/curator5.yaml \ --from-file=actions.yaml=/my/config/actions.yaml \ ; sleep 1
The next iteration will use this configuration.
6.6.5. Using the Curator Action file
The Curator ConfigMap in the openshift-logging
project includes a Curator action file where you configure any Curator action to be run periodically.
However, when you use the action file, OpenShift Container Platform ignores the config.yaml
section of the curator ConfigMap, which is configured to ensure important internal indices do not get deleted by mistake. In order to use the action file, you should add an exclude rule to your configuration to retain these indices. You also must manually add all the other patterns following the steps in this topic.
The actions
and config.yaml
are mutually-exclusive configuration files. Once the actions
file exist, OpenShift Container Platform ignores the config.yaml
file. Using the action file is recommended only for advanced users as using this file can be destructive to the cluster and can cause removal of required indices/settings from Elasticsearch.
Prerequisite
- Cluster logging and Elasticsearch must be installed.
- Set cluster logging to the unmanaged state.
Procedure
To configure Curator to delete indices:
Edit the Curator ConfigMap:
oc edit cm/curator -n openshift-logging
Make the following changes to the
action
file:actions: 1: action: delete_indices 1 description: >- Delete .operations indices older than 30 days. Ignore the error if the filter does not result in an actionable list of indices (ignore_empty_list). See https://www.elastic.co/guide/en/elasticsearch/client/curator/5.2/ex_delete_indices.html options: # Swallow curator.exception.NoIndices exception ignore_empty_list: True # In seconds, default is 300 timeout_override: ${CURATOR_TIMEOUT} # Don't swallow any other exceptions continue_if_exception: False # Optionally disable action, useful for debugging disable_action: False # All filters are bound by logical AND filters: 2 - filtertype: pattern kind: regex value: '^\.operations\..*$' exclude: False 3 - filtertype: age # Parse timestamp from index name source: name direction: older timestring: '%Y.%m.%d' unit: days unit_count: 30 exclude: False
- 1
- Specify
delete_indices
to delete the specified index. - 2
- Use the
filers
parameters to specify the index to be deleted. See the Elastic Search curator documentation for information on these parameters. - 3
- Specify
false
to allow the index to be deleted.
6.7. Configuring Fluentd
OpenShift Container Platform uses Fluentd to collect operations and application logs from your cluster which OpenShift Container Platform enriches with Kubernetes Pod and Namespace metadata.
You can configure log rotation, log location, use an external log aggregator, and make other configurations.
You must set cluster logging to Unmanaged state before performing these configurations, unless otherwise noted. For more information, see Changing the cluster logging management state.
6.7.1. Viewing Fluentd pods
You can use the oc get pods -o wide
command to see the nodes where the Fluentd pod are deployed.
Procedure
Run the following command in the openshift-logging
project:
$ oc get pods -o wide | grep fluentd NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE fluentd-5mr28 1/1 Running 0 4m56s 10.129.2.12 ip-10-0-164-233.ec2.internal <none> fluentd-cnc4c 1/1 Running 0 4m56s 10.128.2.13 ip-10-0-155-142.ec2.internal <none> fluentd-nlp8z 1/1 Running 0 4m56s 10.131.0.13 ip-10-0-138-77.ec2.internal <none> fluentd-rknlk 1/1 Running 0 4m56s 10.128.0.33 ip-10-0-128-130.ec2.internal <none> fluentd-rsm49 1/1 Running 0 4m56s 10.129.0.37 ip-10-0-163-191.ec2.internal <none> fluentd-wjt8s 1/1 Running 0 4m56s 10.130.0.42 ip-10-0-156-251.ec2.internal <none>
6.7.2. Viewing Fluentd logs
How you view logs depends upon the LOGGING_FILE_PATH
setting.
If
LOGGING_FILE_PATH
points to a file, the default, use the logs utility, from the project, where the pod is located, to print out the contents of Fluentd log files:$ oc exec <any-fluentd-pod> -- logs 1
- 1
- Specify the name of a Fluentd pod. Note the space before
logs
.
For example:
$ oc exec fluentd-ht42r -n openshift-logging -- logs
To view the current setting:
oc -n openshift-logging set env daemonset/fluentd --list | grep LOGGING_FILE_PATH
If you are using
LOGGING_FILE_PATH=console
, Fluentd writes logs to stdout/stderr`. You can retrieve the logs with theoc logs [-f] <pod_name>
command, where the-f
is optional, from the project where the pod is located.$ oc logs -f <any-fluentd-pod> 1
- 1
- Specify the name of a Fluentd pod. Use the
-f
option to follow what is being written into the logs.
For example
$ oc logs -f fluentd-ht42r -n openshift-logging
The contents of log files are printed out, starting with the oldest log.
6.7.3. Configure Fluentd CPU and memory limits
Each component specification allows for adjustments to both the CPU and memory limits.
Procedure
Edit the Cluster Logging Custom Resource (CR) in the
openshift-logging
project:$ oc edit ClusterLogging instance
$ oc edit ClusterLogging instance apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "instance" .... spec: collection: logs: fluentd: resources: limits: 1 cpu: 250m memory: 1Gi requests: cpu: 250m memory: 1Gi
- 1
- Specify the CPU and memory limits as needed. The values shown are the default values.
6.7.4. Configuring Fluentd log location
Fluentd writes logs to a specified file or to the default location, /var/log/fluentd/fluentd.log
, based on the LOGGING_FILE_PATH
environment variable.
Prerequisite
Set cluster logging to the unmanaged state.
Procedure
To set the output location for the Fluentd logs:
Edit the
LOGGING_FILE_PATH
parameter in thefluentd
daemonset. You can specify a particular file orconsole
:spec: template: spec: containers: env: - name: LOGGING_FILE_PATH value: console 1 LOGGING_FILE_PATH= 2
- 1
- Specify the log output method:
-
use
console
to use the Fluentd default location. Retrieve the logs with theoc logs [-f] <pod_name>
command. use
<path-to-log/fluentd.log> to sends the log output to the specified file. Retrieve the logs with the `oc exec <pod_name> — logs
command. This is the default setting.Or, use the CLI:
oc -n openshift-logging set env daemonset/fluentd LOGGING_FILE_PATH=console
-
use
6.7.5. Throttling Fluentd logs
For projects that are especially verbose, an administrator can throttle down the rate at which the logs are read in by Fluentd before being processed. By throttling, you deliberately slow down the rate at which you are reading logs, so Kibana might take longer to display records.
Throttling can contribute to log aggregation falling behind for the configured projects; log entries can be lost if a pod is deleted before Fluentd catches up.
Throttling does not work when using the systemd journal as the log source. The throttling implementation depends on being able to throttle the reading of the individual log files for each project. When reading from the journal, there is only a single log source, no log files, so no file-based throttling is available. There is not a method of restricting the log entries that are read into the Fluentd process.
Prerequisite
Set cluster logging to the unmanaged state.
Procedure
To configure Fluentd to restrict specific projects, edit the throttle configuration in the Fluentd ConfigMap after deployment:
$ oc edit configmap/fluentd
The format of the throttle-config.yaml key is a YAML file that contains project names and the desired rate at which logs are read in on each node. The default is 1000 lines at a time per node. For example:
throttle-config.yaml: | - opensift-logging: read_lines_limit: 10 - .operations: read_lines_limit: 100
6.7.6. Understanding Buffer Chunk Limiting for Fluentd
If the Fluentd logger is unable to keep up with a high number of logs, it will need to switch to file buffering to reduce memory usage and prevent data loss.
Fluentd file buffering stores records in chunks. Chunks are stored in buffers.
The Fluentd buffer_chunk_limit
is determined by the environment variable BUFFER_SIZE_LIMIT
, which has the default value 8m
. The file buffer size per output is determined by the environment variable FILE_BUFFER_LIMIT
, which has the default value 256Mi
. The permanent volume size must be larger than FILE_BUFFER_LIMIT
multiplied by the output.
On the Fluentd pods, permanent volume /var/lib/fluentd should be prepared by the PVC or hostmount, for example. That area is then used for the file buffers.
The buffer_type
and buffer_path
are configured in the Fluentd configuration files as follows:
$ egrep "buffer_type|buffer_path" *.conf output-es-config.conf: buffer_type file buffer_path `/var/lib/fluentd/buffer-output-es-config` output-es-ops-config.conf: buffer_type file buffer_path `/var/lib/fluentd/buffer-output-es-ops-config`
The Fluentd buffer_queue_limit
is the value of the variable BUFFER_QUEUE_LIMIT
. This value is 32
by default.
The environment variable BUFFER_QUEUE_LIMIT
is calculated as (FILE_BUFFER_LIMIT / (number_of_outputs * BUFFER_SIZE_LIMIT))
.
If the BUFFER_QUEUE_LIMIT
variable has the default set of values:
-
FILE_BUFFER_LIMIT = 256Mi
-
number_of_outputs = 1
-
BUFFER_SIZE_LIMIT = 8Mi
The value of buffer_queue_limit
will be 32
. To change the buffer_queue_limit
, you must change the value of FILE_BUFFER_LIMIT
.
In this formula, number_of_outputs
is 1
if all the logs are sent to a single resource, and it is incremented by 1
for each additional resource. For example, the value of number_of_outputs
is:
-
1
- if all logs are sent to a single Elasticsearch pod -
2
- if application logs are sent to an Elasticsearch pod and ops logs are sent to another Elasticsearch pod -
4
- if application logs are sent to an Elasticsearch pod, ops logs are sent to another Elasticsearch pod, and both of them are forwarded to other Fluentd instances
6.7.7. Configuring Fluentd JSON parsing
You can configure Fluentd to inspect each log message to determine if the message is in JSON format and merge the message into the JSON payload document posted to Elasticsearch. This feature is disabled by default.
You can enable or disable this feature by editing the MERGE_JSON_LOG
environment variable in the fluentd daemonset.
Enabling this feature comes with risks, including:
- Possible log loss due to Elasticsearch rejecting documents due to inconsistent type mappings.
- Potential buffer storage leak caused by rejected message cycling.
- Overwrite of data for field with same names.
The features in this topic should be used by only experienced Fluentd and Elasticsearch users.
Prerequisites
Set cluster logging to the unmanaged state.
Procedure
Use the following command to enable this feature:
oc set env ds/fluentd MERGE_JSON_LOG=true 1
- 1
- Set this to
false
to disable this feature ortrue
to enable this feature.
Setting MERGE_JSON_LOG and CDM_UNDEFINED_TO_STRING
If you set the MERGE_JSON_LOG
and CDM_UNDEFINED_TO_STRING
enviroment variables to true
, you might receive an Elasticsearch 400 error. The error occurs because when`MERGE_JSON_LOG=true`, Fluentd adds fields with data types other than string. When you set CDM_UNDEFINED_TO_STRING=true
, Fluentd attempts to add those fields as a string value resulting in the Elasticsearch 400 error. The error clears when the indices roll over for the next day.
When Fluentd rolls over the indices for the next day’s logs, it will create a brand new index. The field definitions are updated and you will not get the 400 error.
Records that have hard errors, such as schema violations, corrupted data, and so forth, cannot be retried. Fluent sends the records for error handling. If you add a <label @ERROR>
section to your Fluentd config, as the last <label>, you can handle these records as needed.
For example:
data: fluent.conf: .... <label @ERROR> <match **> @type file path /var/log/fluent/dlq time_slice_format %Y%m%d time_slice_wait 10m time_format %Y%m%dT%H%M%S%z compress gzip </match> </label>
This section writes error records to the Elasticsearch dead letter queue (DLQ) file. See the fluentd documentation for more information about the file output.
Then you can edit the file to clean up the records manually, edit the file to use with the Elasticsearch /_bulk index
API and use cURL to add those records. For more information on Elasticsearch Bulk API, see the Elasticsearch documentation.
6.7.8. Configuring how the log collector normalizes logs
Cluster Logging uses a specific data model, like a database schema, to store log records and their metadata in the logging store. There are some restrictions on the data:
-
There must be a
"message"
field containing the actual log message. -
There must be a
"@timestamp"
field containing the log record timestamp in RFC 3339 format, preferably millisecond or better resolution. -
There must be a
"level"
field with the log level, such aserr
,info
,unknown
, and so forth.
For more information on the data model, see Exported Fields.
Because of these requirements, conflicts and inconsistencies can arise with log data collected from different subsystems.
For example, if you use the MERGE_JSON_LOG
feature (MERGE_JSON_LOG=true
), it can be extremely useful to have your applications log their output in JSON, and have the log collector automatically parse and index the data in Elasticsearch. However, this leads to several problems, including:
- field names can be empty, or contain characters that are illegal in Elasticsearch;
- different applications in the same namespace might output the same field name with different value data types;
- applications might emit too many fields;
- fields may conflict with the cluster logging built-in fields.
You can configure how cluster logging treats fields from disparate sources by editing the log collector daemonset, Fluentd or Rsyslog, and setting environment variables in the table below.
Undefined fields. One of the problems with log data from disparate systems is that some fields might be unknown to the ViaQ data model. Such fields are called undefined. ViaQ requires all top-level fields to be defined and described.
Use the parameters to configure how OpenShift Container Platform moves any undefined fields under a top-level field called
undefined
to avoid conflicting with the well known ViaQ top-level fields. You can add undefined fields to the top-level fields and move others to anundefined
container.You can also replace special characters in undefined fields and convert undefined fields to their JSON string representation. Coverting to JSON string preserves the structure of the value, so that you can retrieve the value later and convert it back to a map or an array.
-
Simple scalar values like numbers and booleans are changed to a quoted string. For example:
10
becomes"10"
,3.1415
becomes"3.1415"`
,false
becomes"false"
. -
Map/dict values and array values are converted to their JSON string representation:
"mapfield":{"key":"value"}
becomes"mapfield":"{\"key\":\"value\"}"
and"arrayfield":[1,2,"three"]
becomes"arrayfield":"[1,2,\"three\"]"
.
-
Simple scalar values like numbers and booleans are changed to a quoted string. For example:
Defined fields. You can also configure which defined fields appear in the top levels of the logs.
The default top-level fields, defined through the
CDM_DEFAULT_KEEP_FIELDS
parameter, areCEE
,time
,@timestamp
,aushape
,ci_job
,collectd
,docker
,fedora-ci
,file
,foreman
,geoip
,hostname
,ipaddr4
,ipaddr6
,kubernetes
,level
,message
,namespace_name
,namespace_uuid
,offset
,openstack
,ovirt
,pid
,pipeline_metadata
,rsyslog
,service
,systemd
,tags
,testcase
,tlog
,viaq_msg_id
.Any fields not included in
${CDM_DEFAULT_KEEP_FIELDS}
or${CDM_EXTRA_KEEP_FIELDS}
are moved to${CDM_UNDEFINED_NAME}
ifCDM_USE_UNDEFINED
istrue
.NoteThe
CDM_DEFAULT_KEEP_FIELDS
parameter is for only advanced users, or if you are instructed to do so by Red Hat support.- Empty fields. You can determine which empty fields to retain from disparate logs.
Parameters | Definition | Example |
---|---|---|
|
Specify an extra set of defined fields to be kept at the top level of the logs in addition to the |
|
| Specify fields to retain even if empty in CSV format. Empty defined fields not specified are dropped. The default is "message", keep empty messages. |
|
|
Set to |
|
|
Specify a name for the undefined top level field if using |
|
|
If the number of undefined fields is greater than this number, all undefined fields are converted to their JSON string representation and stored in the Note
This parameter is honored even if |
|
|
Set to |
|
|
Specify a character to use in place of a dot character '.' in an undefined field. |
|
If you set the MERGE_JSON_LOG
parameter in the log collector daemonset and CDM_UNDEFINED_TO_STRING
environment variables to true, you might receive an Elasticsearch 400 error. The error occurs because when`MERGE_JSON_LOG=true`, the log collector adds fields with data types other than string. When you set CDM_UNDEFINED_TO_STRING=true
, the log collector attempts to add those fields as a string value resulting in the Elasticsearch 400 error. The error clears when the log collector rolls over the indices for the next day’s logs
When the log collector rolls over the indices, it creates a brand new index. The field definitions are updated and you will not get the 400 error.
Procedure
Use the CDM_*
parameters to configure undefined and empty field processing.
Configure how to process fields, as needed:
-
Specify the fields to move using
CDM_EXTRA_KEEP_FIELDS
. -
Specify any empty fields to retain in the
CDM_KEEP_EMPTY_FIELDS
parameter in CSV format.
-
Specify the fields to move using
Configure how to process undefined fields, as needed:
-
Set
CDM_USE_UNDEFINED
totrue
to move undefined fields to the top-levelundefined
field: -
Specify a name for the undefined fields using the
CDM_UNDEFINED_NAME
parameter. -
Set
CDM_UNDEFINED_MAX_NUM_FIELDS
to a value other than the default-1
, to set an upper bound on the number of undefined fields in a single record.
-
Set
-
Specify
CDM_UNDEFINED_DOT_REPLACE_CHAR
to change any dot.
characters in an undefined field name to another character. For example, ifCDM_UNDEFINED_DOT_REPLACE_CHAR=@@@
and there is a field namedfoo.bar.baz
the field is transformed intofoo@@@bar@@@baz
. -
Set
UNDEFINED_TO_STRING
totrue
to convert undefined fields to their JSON string representation.
If you configure the CDM_UNDEFINED_TO_STRING
or CDM_UNDEFINED_MAX_NUM_FIELDS
parameters, you use the CDM_UNDEFINED_NAME
to change the undefined field name. This field is needed because CDM_UNDEFINED_TO_STRING
or CDM_UNDEFINED_MAX_NUM_FIELDS
could change the value type of the undefined field. When CDM_UNDEFINED_TO_STRING
or CDM_UNDEFINED_MAX_NUM_FIELDS
is set to true and there are more undefined fields in a log, the value type becomes string
. Elasticsearch stops accepting records if the value type is changed, for example, from JSON to JSON string.
For example, when CDM_UNDEFINED_TO_STRING
is false
or CDM_UNDEFINED_MAX_NUM_FIELDS
is the default, -1
, the value type of the undefined field is json
. If you change CDM_UNDEFINED_MAX_NUM_FIELDS
to a value other than default and there are more undefined fields in a log, the value type becomes string
(json string). Elasticsearch stops accepting records if the value type is changed.
6.7.9. Configuring Fluentd using environment variables
You can use environment variables to modify your Fluentd configuration.
Prerequisite
Set cluster logging to the unmanaged state.
Procedure
Set any of the Fluentd environment variables as needed:
oc set env ds/fluentd <env-var>=<value>
For example:
oc set env ds/fluentd LOGGING_FILE_AGE=30
6.8. Sending OpenShift Container Platform logs to external devices
You can send Elasticsearch logs to external devices, such as an externally-hosted Elasticsearch instance or an external syslog server. You can also configure Fluentd to send logs to an external log aggregator.
You must set cluster logging to Unmanaged state before performing these configurations, unless otherwise noted. For more information, see Changing the cluster logging management state.
6.8.1. Configuring Fluentd to send logs to an external Elasticsearch instance
Fluentd sends logs to the value of the ES_HOST
, ES_PORT
, OPS_HOST
, and OPS_PORT
environment variables of the Elasticsearch deployment configuration. The application logs are directed to the ES_HOST
destination, and operations logs to OPS_HOST
.
Sending logs directly to an AWS Elasticsearch instance is not supported. Use Fluentd Secure Forward to direct logs to an instance of Fluentd that you control and that is configured with the fluent-plugin-aws-elasticsearch-service
plug-in.
Prerequisite
- Cluster logging and Elasticsearch must be installed.
- Set cluster logging to the unmanaged state.
Procedure
To direct logs to a specific Elasticsearch instance:
Edit the
fluentd
DaemonSet in the openshift-logging project:$ oc edit ds/fluentd spec: template: spec: containers: env: - name: ES_HOST value: elasticsearch - name: ES_PORT value: '9200' - name: ES_CLIENT_CERT value: /etc/fluent/keys/app-cert - name: ES_CLIENT_KEY value: /etc/fluent/keys/app-key - name: ES_CA value: /etc/fluent/keys/app-ca - name: OPS_HOST value: elasticsearch - name: OPS_PORT value: '9200' - name: OPS_CLIENT_CERT value: /etc/fluent/keys/infra-cert - name: OPS_CLIENT_KEY value: /etc/fluent/keys/infra-key - name: OPS_CA value: /etc/fluent/keys/infra-ca
-
Set
ES_HOST
andOPS_HOST
to the same destination, while ensuring thatES_PORT
andOPS_PORT
also have the same value for an external Elasticsearch instance to contain both application and operations logs. - Configure your externally-hosted Elasticsearch instance for TLS. Only externally-hosted Elasticsearch instances that use Mutual TLS are allowed.
If you are not using the provided Kibana and Elasticsearch images, you will not have the same multi-tenant capabilities and your data will not be restricted by user access to a particular project.
6.8.2. Configuring Fluentd to send logs to an external syslog server
Use the fluent-plugin-remote-syslog
plug-in on the host to send logs to an external syslog server.
Prerequisite
Set cluster logging to the unmanaged state.
Procedure
Set environment variables in the
fluentd
daemonset in theopenshift-logging
project:spec: template: spec: containers: - name: fluentd image: 'registry.redhat.io/openshift4/ose-logging-fluentd:v4.1' env: - name: REMOTE_SYSLOG_HOST 1 value: host1 - name: REMOTE_SYSLOG_HOST_BACKUP value: host2 - name: REMOTE_SYSLOG_PORT_BACKUP value: 5555
- 1
- The desired remote syslog host. Required for each host.
This will build two destinations. The syslog server on
host1
will be receiving messages on the default port of514
, whilehost2
will be receiving the same messages on port5555
.Alternatively, you can configure your own custom the
fluentd
daemonset in theopenshift-logging
project.Fluentd Environment Variables
Parameter Description USE_REMOTE_SYSLOG
Defaults to
false
. Set totrue
to enable use of thefluent-plugin-remote-syslog
gemREMOTE_SYSLOG_HOST
(Required) Hostname or IP address of the remote syslog server.
REMOTE_SYSLOG_PORT
Port number to connect on. Defaults to
514
.REMOTE_SYSLOG_SEVERITY
Set the syslog severity level. Defaults to
debug
.REMOTE_SYSLOG_FACILITY
Set the syslog facility. Defaults to
local0
.REMOTE_SYSLOG_USE_RECORD
Defaults to
false
. Set totrue
to use the record’s severity and facility fields to set on the syslog message.REMOTE_SYSLOG_REMOVE_TAG_PREFIX
Removes the prefix from the tag, defaults to
''
(empty).REMOTE_SYSLOG_TAG_KEY
If specified, uses this field as the key to look on the record, to set the tag on the syslog message.
REMOTE_SYSLOG_PAYLOAD_KEY
If specified, uses this field as the key to look on the record, to set the payload on the syslog message.
REMOTE_SYSLOG_TYPE
Set the transport layer protocol type. Defaults to
syslog_buffered
, which sets the TCP protocol. To switch to UDP, set this tosyslog
.WarningThis implementation is insecure, and should only be used in environments where you can guarantee no snooping on the connection.
6.8.3. Configuring Fluentd to send logs to an external log aggregator
You can configure Fluentd to send a copy of its logs to an external log aggregator, and not the default Elasticsearch, using the out_forward plug-in. From there, you can further process log records after the locally hosted Fluentd has processed them.
The forward
plug-in is supported by Fluentd only. The out_forward plug-in implements the client side (sender) and the in_forward plug-in implements the server side (receiver).
To configure OpenShift Container Platform to send logs using out_forward, create a ConfigMap called secure-forward
in the openshift-logging
namespace that points to a receiver. On the receiver, configure the in_forward plug-in to receive the logs from OpenShift Container Platform. For more information on using the in_forward plug-in, see the Fluentd documentation.
Default secure-forward.conf
section
# <store> # @type forward # <security> # self_hostname ${hostname} # ${hostname} is a placeholder. # shared_key <shared_key_between_forwarder_and_forwardee> # </security> # transport tls # tls_verify_hostname true # Set false to ignore server cert hostname. # tls_cert_path /path/for/certificate/ca_cert.pem # <buffer> # @type file # path '/var/lib/fluentd/forward' # queued_chunks_limit_size "#{ENV['BUFFER_QUEUE_LIMIT'] || '1024' }" # chunk_limit_size "#{ENV['BUFFER_SIZE_LIMIT'] || '1m' }" # flush_interval "#{ENV['FORWARD_FLUSH_INTERVAL'] || '5s'}" # flush_at_shutdown "#{ENV['FLUSH_AT_SHUTDOWN'] || 'false'}" # flush_thread_count "#{ENV['FLUSH_THREAD_COUNT'] || 2}" # retry_max_interval "#{ENV['FORWARD_RETRY_WAIT'] || '300'}" # retry_forever true # # the systemd journald 0.0.8 input plugin will just throw away records if the buffer # # queue limit is hit - 'block' will halt further reads and keep retrying to flush the # # buffer to the remote - default is 'exception' because in_tail handles that case # overflow_action "#{ENV['BUFFER_QUEUE_FULL_ACTION'] || 'exception'}" # </buffer> # <server> # host server.fqdn.example.com # or IP # port 24284 # </server> # <server> # host 203.0.113.8 # ip address to connect # name server.fqdn.example.com # The name of the server. Used for logging and certificate verification in TLS transport (when host is address). # </server> # </store>
Procedure
To send a copy of Fluentd logs to an external log aggregator:
Edit the
secure-forward.conf
section of the Fluentd configuration map:$ oc edit configmap/fluentd -n openshift-logging
Enter the name, host, and port for your external Fluentd server:
# <server> # host server.fqdn.example.com # or IP # port 24284 # </server> # <server> # host 203.0.113.8 # ip address to connect # name server.fqdn.example.com # The name of the server. Used for logging and certificate verification in TLS transport (when host is address). # </server>
For example:
<server> name externalserver1 1 host 192.168.1.1 2 port 24224 3 </server> <server> 4 name externalserver1 host 192.168.1.2 port 24224 </server> </store>
Add the path to your CA certificate and private key to the
secure-forward.conf
section:# <security> # self_hostname ${hostname} # ${hostname} is a placeholder. 1 # shared_key <shared_key_between_forwarder_and_forwardee> 2 # </security> # tls_cert_path /path/for/certificate/ca_cert.pem 3
For example:
<security> self_hostname client.fqdn.local shared_key cluster_logging_key </security> tls_cert_path /etc/fluent/keys/ca.crt
To use mTLS, see the Fluentd documentation for information about client certificate and key parameters and other settings.
Add certificates to be used in
secure-forward.conf
to the existing secret that is mounted on the Fluentd pods. Theyour_ca_cert
andyour_private_key
values must match what is specified insecure-forward.conf
inconfigmap/logging-fluentd
:$ oc patch secrets/fluentd --type=json \ --patch "[{'op':'add','path':'/data/your_ca_cert','value':'$(base64 -w0 /path/to/your_ca_cert.pem)'}]" $ oc patch secrets/fluentd --type=json \ --patch "[{'op':'add','path':'/data/your_private_key','value':'$(base64 -w0 /path/to/your_private_key.pem)'}]"
NoteReplace
your_private_key
with a generic name. This is a link to the JSON path, not a path on your host system.For example:
$ oc patch secrets/fluentd --type=json \ --patch "[{'op':'add','path':'/data/ca.crt','value':'$(base64 -w0 /etc/fluent/keys/ca.crt)'}]" $ oc patch secrets/fluentd --type=json \ --patch "[{'op':'add','path':'/data/ext-agg','value':'$(base64 -w0 /etc/fluent/keys/ext-agg.pem)'}]"
Configure the
secure-forward.conf
file on the external aggregator to accept messages securely from Fluentd.When configuring the external aggregator, it must be able to accept messages securely from Fluentd.
You can find further explanation of how to set up the inforward plugin and the out_forward plugin.
6.9. Configuring systemd-journald and rsyslog
Because Fluentd and rsyslog read from the journal, and the journal default settings are very low, journal entries can be lost because the journal cannot keep up with the logging rate from system services.
We recommend setting RateLimitInterval=1s
and RateLimitBurst=10000
(or even higher if necessary) to prevent the journal from losing entries.
6.9.1. Configuring systemd-journald for cluster logging
As you scale up your project, the default logging environment might need some adjustments.
For example, if you are missing logs, you might have to increase the rate limits for journald. You can adjust the number of messages to retain for a specified period of time to ensure that cluster logging does not use excessive resources without dropping logs.
You can also determine if you want the logs compressed, how long to retain logs, how or if the logs are stored, and other settings.
Procedure
Create a
journald.conf
file with the required settings:Compress=no 1 ForwardToConsole=yes 2 ForwardToSyslog=no 3 MaxRetentionSec=30s 4 RateLimitBurst=10000 5 RateLimitInterval=1s 6 Storage=volatile 7 SyncIntervalSec=1s 8 SystemMaxUse=8g 9 SystemKeepFree=20% 10 SystemMaxFileSize10M 11
- 1
- Specify whether you want logs compressed before they are written to the file system. Specify
yes
to compress the message orno
to not compress. The default isyes
. - 2 3
- Configure whether to forward log messages. Defaults to
no
for each. Specify:-
ForwardToConsole
to forward logs to the system console. -
ForwardToKsmg
to forward logs to the kernel log buffer. -
ForwardToSyslog
to forward to a syslog daemon. -
ForwardToWall
to forward messages as wall messages to all logged-in users.
-
- 4
- Specify the maximum time to store journal entries. Enter digits to specify seconds. Or include a unit: "year", "month", "week", "day", "h" or "m". Enter
0
to disable. The default is1month
. - 5 6
- Configure rate limiting. If, during the time interval defined by
RateLimitIntervalSec
, more logs than specified inRateLimitBurst
are received, all further messages within the interval are dropped until the interval is over. It is recommended to setRateLimitInterval=1s
andRateLimitBurst=10000
, which are the defaults. - 7
- Specify how logs are stored. The default is
persistent
:-
volatile
to store logs in memory in/var/log/journal/
. -
persistent
to store logs to disk in/var/log/journal/
. systemd creates the directory if it does not exist. -
auto
to store logs in in/var/log/journal/
if the directory exists. If it does not exist, systemd temporarily stores logs in/run/systemd/journal
. -
none
to not store logs. systemd drops all logs.
-
- 8
- Specify the timeout before synchronizing journal files to disk for ERR, WARNING, NOTICE, INFO, and DEBUG logs. systemd immediately syncs after receiving a CRIT, ALERT, or EMERG log. The default is
1s
. - 9
- Specify the maximum size the journal can use. The default is
8g
. - 10
- Specify how much disk space systemd must leave free. The default is
20%
. - 11
- Specify the maximum size for individual journal files stored persistently in
/var/log/journal
. The default is10M
.NoteIf you are removing the rate limit, you might see increased CPU utilization on the system logging daemons as it processes any messages that would have previously been throttled.
For more information on systemd settings, see https://www.freedesktop.org/software/systemd/man/journald.conf.html. The default settings listed on that page might not apply to OpenShift Container Platform.
Convert the
journal.conf
file to base64:$ export jrnl_cnf=$( cat /journald.conf | base64 -w0 )
Create a new MachineConfig for master or worker and add the
journal.conf
parameters:For example:
... config: storage: files: - contents: source: data:text/plain;charset=utf-8;base64,${jrnl_cnf} verification: {} filesystem: root mode: 0644 1 path: /etc/systemd/journald.conf 2 systemd: {}
Create the MachineConfig:
$ oc apply -f <filename>.yaml
The controller detects the new MachineConfig and generates a new
rendered-worker-<hash>
version.Monitor the status of the rollout of the new rendered configuration to each node:
$ oc describe machineconfigpool/worker Name: worker Namespace: Labels: machineconfiguration.openshift.io/mco-built-in= Annotations: <none> API Version: machineconfiguration.openshift.io/v1 Kind: MachineConfigPool ... Conditions: Message: Reason: All nodes are updating to rendered-worker-913514517bcea7c93bd446f4830bc64e
Chapter 7. Viewing Elasticsearch status
You can view the status of the Elasticsearch Operator and for a number of Elasticsearch components.
7.1. Viewing Elasticsearch status
You can view the status of your Elasticsearch cluster.
Prerequisites
- Cluster logging and Elasticsearch must be installed.
Procedure
Change to the
openshift-logging
project.$ oc project openshift-logging
To view the Elasticsearch cluster status:
Get the name of the Elasticsearch instance:
$ oc get Elasticsearch NAME AGE elasticsearch 5h9m
Get the Elasticsearch status:
$ oc get Elasticsearch <Elasticsearch-instance> -o yaml
For example:
$ oc get Elasticsearch elasticsearch -n openshift-logging -o yaml
The output includes information similar to the following:
status: 1 clusterHealth: green 2 conditions: 3 ..... nodes: 4 ..... pods: 5 ..... shardAllocationEnabled: "All" 6
- 1
- In the output, the cluster status fields appear in the
status
stanza. - 2
- The status of the Elasticsearch cluster,
green
,red
,yellow
. - 3
- Any status conditions, if present. The Elasticsearch cluster status indicates the reasons from the scheduler if a pod could not be placed. Any events related to the following conditions are shown:
- Container Waiting for both the Elasticsearch and proxy containers,
- Container Terminated for both the Elasticsearch and proxy containers,
- Pod unschedulable. Also, a condition is shown for a number of issues, see Example condition messages.
- 4
- The Elasticsearch nodes in the cluster, with
upgradeStatus
. - 5
- The Elasticsearch client, data, and master pods in the cluster, listed under 'failed`,
notReady
orready
state.
7.1.1. Example condition messages
The following are examples of some condition messages from the Status
section of the Elasticsearch instance.
This status message indicates a node has exceeded the configured low watermark and no shard will be allocated to this node.
status: nodes: - conditions: - lastTransitionTime: 2019-03-15T15:57:22Z message: Disk storage usage for node is 27.5gb (36.74%). Shards will be not be allocated on this node. reason: Disk Watermark Low status: "True" type: NodeStorage deploymentName: example-elasticsearch-cdm-0-1 upgradeStatus: {}
This status message indicates a node has exceeded the configured high watermark and shard will be relocated to other nodes.
status: nodes: - conditions: - lastTransitionTime: 2019-03-15T16:04:45Z message: Disk storage usage for node is 27.5gb (36.74%). Shards will be relocated from this node. reason: Disk Watermark High status: "True" type: NodeStorage deploymentName: example-elasticsearch-cdm-0-1 upgradeStatus: {}
This status message indicates the Elasticsearch node selector in the CR does not match any nodes in the cluster:
status: nodes: - conditions: - lastTransitionTime: 2019-04-10T02:26:24Z message: '0/8 nodes are available: 8 node(s) didn''t match node selector.' reason: Unschedulable status: "True" type: Unschedulable
This status message indicates that the Elasticsearch CR uses a non-existent PVC.
status: nodes: - conditions: - last Transition Time: 2019-04-10T05:55:51Z message: pod has unbound immediate PersistentVolumeClaims (repeated 5 times) reason: Unschedulable status: True type: Unschedulable
This status message indicates that your Elasticsearch cluster does not have enough nodes to support your Elasticsearch redundancy policy.
status: clusterHealth: "" conditions: - lastTransitionTime: 2019-04-17T20:01:31Z message: Wrong RedundancyPolicy selected. Choose different RedundancyPolicy or add more nodes with data roles reason: Invalid Settings status: "True" type: InvalidRedundancy
This status message indicates your cluster has too many master nodes:
status: clusterHealth: green conditions: - lastTransitionTime: '2019-04-17T20:12:34Z' message: >- Invalid master nodes count. Please ensure there are no more than 3 total nodes with master roles reason: Invalid Settings status: 'True' type: InvalidMasters
7.2. Viewing Elasticsearch component status
You can view the status for a number of Elasticsearch components.
- Elasticsearch indices
You can view the status of the Elasticsearch indices.
Get the name of an Elasticsearch pod:
$ oc get pods --selector component=elasticsearch -o name pod/elasticsearch-cdm-1godmszn-1-6f8495-vp4lw pod/elasticsearch-cdm-1godmszn-2-5769cf-9ms2n pod/elasticsearch-cdm-1godmszn-3-f66f7d-zqkz7
Get the status of the indices:
$ oc exec elasticsearch-cdm-1godmszn-1-6f8495-vp4lw -- indices Defaulting container name to elasticsearch. Use 'oc describe pod/elasticsearch-cdm-1godmszn-1-6f8495-vp4lw -n openshift-logging' to see all of the containers in this pod. Wed Apr 10 05:42:12 UTC 2019 health status index uuid pri rep docs.count docs.deleted store.size pri.store.size red open .kibana.647a750f1787408bf50088234ec0edd5a6a9b2ac N7iCbRjSSc2bGhn8Cpc7Jg 2 1 green open .operations.2019.04.10 GTewEJEzQjaus9QjvBBnGg 3 1 2176114 0 3929 1956 green open .operations.2019.04.11 ausZHoKxTNOoBvv9RlXfrw 3 1 1494624 0 2947 1475 green open .kibana 9Fltn1D0QHSnFMXpphZ--Q 1 1 1 0 0 0 green open .searchguard chOwDnQlSsqhfSPcot1Yiw 1 1 5 1 0 0
- Elasticsearch pods
You can view the status of the Elasticsearch pods.
Get the name of a pod:
$ oc get pods --selector component=elasticsearch -o name pod/elasticsearch-cdm-1godmszn-1-6f8495-vp4lw pod/elasticsearch-cdm-1godmszn-2-5769cf-9ms2n pod/elasticsearch-cdm-1godmszn-3-f66f7d-zqkz7
Get the status of a pod:
oc describe pod elasticsearch-cdm-1godmszn-1-6f8495-vp4lw
The output includes the following status information:
.... Status: Running .... Containers: elasticsearch: Container ID: cri-o://b7d44e0a9ea486e27f47763f5bb4c39dfd2 State: Running Started: Mon, 08 Apr 2019 10:17:56 -0400 Ready: True Restart Count: 0 Readiness: exec [/usr/share/elasticsearch/probe/readiness.sh] delay=10s timeout=30s period=5s #success=1 #failure=3 .... proxy: Container ID: cri-o://3f77032abaddbb1652c116278652908dc01860320b8a4e741d06894b2f8f9aa1 State: Running Started: Mon, 08 Apr 2019 10:18:38 -0400 Ready: True Restart Count: 0 .... Conditions: Type Status Initialized True Ready True ContainersReady True PodScheduled True .... Events: <none>
- Elasticsearch deployment configuration
You can view the status of the Elasticsearch deployment configuration.
Get the name of a deployment configuration:
$ oc get deployment --selector component=elasticsearch -o name deployment.extensions/elasticsearch-cdm-1gon-1 deployment.extensions/elasticsearch-cdm-1gon-2 deployment.extensions/elasticsearch-cdm-1gon-3
Get the deployment configuration status:
$ oc describe deployment elasticsearch-cdm-1gon-1
The output includes the following status information:
.... Containers: elasticsearch: Image: registry.redhat.io/openshift4/ose-logging-elasticsearch5:v4.1 Readiness: exec [/usr/share/elasticsearch/probe/readiness.sh] delay=10s timeout=30s period=5s #success=1 #failure=3 .... Conditions: Type Status Reason ---- ------ ------ Progressing Unknown DeploymentPaused Available True MinimumReplicasAvailable .... Events: <none>
- Elasticsearch ReplicaSet
You can view the status of the Elasticsearch ReplicaSet.
Get the name of a replica set:
$ oc get replicaSet --selector component=elasticsearch -o name replicaset.extensions/elasticsearch-cdm-1gon-1-6f8495 replicaset.extensions/elasticsearch-cdm-1gon-2-5769cf replicaset.extensions/elasticsearch-cdm-1gon-3-f66f7d
Get the status of the replica set:
$ oc describe replicaSet elasticsearch-cdm-1gon-1-6f8495
The output includes the following status information:
.... Containers: elasticsearch: Image: registry.redhat.io/openshift4/ose-logging-elasticsearch5:v4.1 Readiness: exec [/usr/share/elasticsearch/probe/readiness.sh] delay=10s timeout=30s period=5s #success=1 #failure=3 .... Events: <none>
Chapter 8. Moving the cluster logging resources with node selectors
You can use node selectors to deploy the Elasticsearch, Kibana, and Curator pods to different nodes.
8.1. Specifying a node for cluster logging components using node selectors
Each component specification allows the component to target a specific node.
Prerequisites
- Cluster logging and Elasticsearch must be installed. These features are not installed by default.
Procedure
Add the desired label to your nodes:
$ oc label <resource> <name> <key>=<value>
For example, to label a node:
$ oc label nodes ip-10-0-142-25.ec2.internal type=elasticsearch
Edit the Cluster Logging Custom Resource in the
openshift-logging
project:$ oc edit ClusterLogging instance apiVersion: "logging.openshift.io/v1" kind: "ClusterLogging" metadata: name: "nodeselector" spec: managementState: "Managed" logStore: type: "elasticsearch" elasticsearch: nodeSelector: 1 logging: es nodeCount: 1 resources: limits: memory: 2Gi requests: cpu: 200m memory: 2Gi storage: size: "20G" storageClassName: "gp2" redundancyPolicy: "ZeroRedundancy" visualization: type: "kibana" kibana: nodeSelector: 2 logging: kibana replicas: 1 curation: type: "curator" curator: nodeSelector: 3 logging: curator schedule: "*/10 * * * *" collection: logs: type: "fluentd" fluentd: nodeSelector: 4 logging: fluentd
Chapter 9. Additional resources
- For more information on node selectors, see: Placing pods on specific nodes using node selectors.
Chapter 10. Manually rolling out Elasticsearch
OpenShift Container Platform supports the Elasticsearch rolling cluster restart. A rolling restart applies appropriate changes to the Elasticsearch cluster without down time (if three masters are configured). The Elasticsearch cluster remains online and operational, with nodes taken offline one at a time.
10.1. Performing an Elasticsearch rolling cluster restart
Perform a rolling restart when you change the elasticsearch
configmap or any of the `elasticsearch-* ` deployment configurations.
Also, a rolling restart is recommended if the nodes on which an Elasticsearch pod runs requires a reboot.
Prerequisite
- Cluster logging and Elasticsearch must be installed.
Procedure
To perform a rolling cluster restart:
Change to the
openshift-logging
project:$ oc project openshift-logging
Use the following command to extract the CA certificate from Elasticsearch and write to the admin-ca file:
$ oc extract secret/elasticsearch --to=. --keys=admin-ca admin-ca
Perform a shard synced flush to ensure there are no pending operations waiting to be written to disk prior to shutting down:
$ oc exec <any_es_pod_in_the_cluster> -c elasticsearch -- curl -s --cacert /etc/elasticsearch/secret/admin-ca --cert /etc/elasticsearch/secret/admin-cert --key /etc/elasticsearch/secret/admin-key -XPOST 'https://localhost:9200/_flush/synced'
For example:
oc exec -c elasticsearch-cdm-5ceex6ts-1-dcd6c4c7c-jpw6 -- curl -s --cacert /etc/elasticsearch/secret/admin-ca --cert /etc/elasticsearch/secret/admin-cert --key /etc/elasticsearch/secret/admin-key -XPOST 'https://localhost:9200/_flush/synced'
Prevent shard balancing when purposely bringing down nodes using the OpenShift Container Platform es_util tool:
$ oc exec <any_es_pod_in_the_cluster> -c elasticsearch -- es_util --query=_cluster/settings -XPUT 'https://localhost:9200/_cluster/settings' -d '{ "transient": { "cluster.routing.allocation.enable" : "none" } }'
For example:
$ oc exec elasticsearch-cdm-5ceex6ts-1-dcd6c4c7c-jpw6 -c elasticsearch -- es_util --query=_cluster/settings?pretty=true -XPUT 'https://localhost:9200/_cluster/settings' -d '{ "transient": { "cluster.routing.allocation.enable" : "none" } }' { "acknowledged" : true, "persistent" : { }, "transient" : { "cluster" : { "routing" : { "allocation" : { "enable" : "none" } } } }
Once complete, for each deployment you have for an ES cluster:
By default, the OpenShift Container Platform Elasticsearch cluster blocks rollouts to their nodes. Use the following command to allow rollouts and allow the pod to pick up the changes:
$ oc rollout resume deployment/<deployment-name>
For example:
$ oc rollout resume deployment/elasticsearch-cdm-0-1 deployment.extensions/elasticsearch-cdm-0-1 resumed
A new pod is deployed. Once the pod has a ready container, you can move on to the next deployment.
$ oc get pods | grep elasticsearch-* NAME READY STATUS RESTARTS AGE elasticsearch-cdm-5ceex6ts-1-dcd6c4c7c-jpw6k 2/2 Running 0 22h elasticsearch-cdm-5ceex6ts-2-f799564cb-l9mj7 2/2 Running 0 22h elasticsearch-cdm-5ceex6ts-3-585968dc68-k7kjr 2/2 Running 0 22h
Once complete, reset the pod to disallow rollouts:
$ oc rollout pause deployment/<deployment-name>
For example:
$ oc rollout pause deployment/elasticsearch-cdm-0-1 deployment.extensions/elasticsearch-cdm-0-1 paused
Check that the Elasticsearch cluster is in
green
state:$ oc exec <any_es_pod_in_the_cluster> -c elasticsearch -- es_util --query=_cluster/health?pretty=true
NoteIf you performed a rollout on the Elasticsearch pod you used in the previous commands, the pod no longer exists and you need a new pod name here.
For example:
$ oc exec elasticsearch-cdm-5ceex6ts-1-dcd6c4c7c-jpw6 -c elasticsearch -- es_util --query=_cluster/health?pretty=true { "cluster_name" : "elasticsearch", "status" : "green", 1 "timed_out" : false, "number_of_nodes" : 3, "number_of_data_nodes" : 3, "active_primary_shards" : 8, "active_shards" : 16, "relocating_shards" : 0, "initializing_shards" : 0, "unassigned_shards" : 1, "delayed_unassigned_shards" : 0, "number_of_pending_tasks" : 0, "number_of_in_flight_fetch" : 0, "task_max_waiting_in_queue_millis" : 0, "active_shards_percent_as_number" : 100.0 }
- 1
- Make sure this parameter is
green
before proceeding.
- If you changed the Elasticsearch configuration map, repeat these steps for each Elasticsearch pod.
Once all the deployments for the cluster have been rolled out, re-enable shard balancing:
$ oc exec <any_es_pod_in_the_cluster> -c elasticsearch -- es_util --query=_cluster/settings -XPUT 'https://localhost:9200/_cluster/settings' -d '{ "transient": { "cluster.routing.allocation.enable" : "none" } }'
For example:
$ oc exec elasticsearch-cdm-5ceex6ts-1-dcd6c4c7c-jpw6 -c elasticsearch -- es_util --query=_cluster/settings?pretty=true -XPUT 'https://localhost:9200/_cluster/settings' -d '{ "transient": { "cluster.routing.allocation.enable" : "all" } }' { "acknowledged" : true, "persistent" : { }, "transient" : { "cluster" : { "routing" : { "allocation" : { "enable" : "all" } } } } }
Chapter 11. Troubleshooting Kibana
Using the Kibana console with OpenShift Container Platform can cause problems that are easily solved, but are not accompanied with useful error messages. Check the following troubleshooting sections if you are experiencing any problems when deploying Kibana on OpenShift Container Platform.
11.1. Troubleshooting a Kubernetes login loop
The OAuth2 proxy on the Kibana console must share a secret with the master host’s OAuth2 server. If the secret is not identical on both servers, it can cause a login loop where you are continuously redirected back to the Kibana login page.
Procedure
To fix this issue:
Run the following command to delete the current OAuthClient:
$ oc delete oauthclient/kibana-proxy
11.2. Troubleshooting a Kubernetes cryptic error when viewing the Kibana console
When attempting to visit the Kibana console, you may receive a browser error instead:
{"error":"invalid_request","error_description":"The request is missing a required parameter, includes an invalid parameter value, includes a parameter more than once, or is otherwise malformed."}
This can be caused by a mismatch between the OAuth2 client and server. The return address for the client must be in a whitelist so the server can securely redirect back after logging in.
Fix this issue by replacing the OAuthClient entry.
Procedure
To replace the OAuthClient entry:
Run the following command to delete the current OAuthClient:
$ oc delete oauthclient/kibana-proxy
If the problem persists, check that you are accessing Kibana at a URL listed in the OAuth client. This issue can be caused by accessing the URL at a forwarded port, such as 1443 instead of the standard 443 HTTPS port. You can adjust the server whitelist by editing the OAuth client:
$ oc edit oauthclient/kibana-proxy
11.3. Troubleshooting a Kubernetes 503 error when viewing the Kibana console
If you receive a proxy error when viewing the Kibana console, it could be caused by one of two issues:
Kibana might not be recognizing pods. If Elasticsearch is slow in starting up, Kibana may timeout trying to reach it. Check whether the relevant service has any endpoints:
$ oc describe service kibana Name: kibana [...] Endpoints: <none>
If any Kibana pods are live, endpoints are listed. If they are not, check the state of the Kibana pods and deployment. You might have to scale the deployment down and back up again.
The route for accessing the Kibana service is masked. This can happen if you perform a test deployment in one project, then deploy in a different project without completely removing the first deployment. When multiple routes are sent to the same destination, the default router will only route to the first created. Check the problematic route to see if it is defined in multiple places:
$ oc get route --all-namespaces --selector logging-infra=support
Chapter 12. Exported fields
These are the fields exported by the logging system and available for searching from Elasticsearch and Kibana. Use the full, dotted field name when searching. For example, for an Elasticsearch /_search URL, to look for a Kubernetes Pod name, use /_search/q=kubernetes.pod_name:name-of-my-pod
.
The following sections describe fields that may not be present in your logging store. Not all of these fields are present in every record. The fields are grouped in the following categories:
-
exported-fields-Default
-
exported-fields-rsyslog
-
exported-fields-systemd
-
exported-fields-kubernetes
-
exported-fields-pipeline_metadata
-
exported-fields-ovirt
-
exported-fields-aushape
-
exported-fields-tlog
12.1. Default exported fields
These are the default fields exported by the logging system and available for searching from Elasticsearch and Kibana. The default fields are Top Level and collectd*
Top Level Fields
The top level fields are common to every application, and may be present in every record. For the Elasticsearch template, top level fields populate the actual mappings of default
in the template’s mapping section.
Parameter | Description |
---|---|
|
The UTC value marking when the log payload was created, or when the log payload was first collected if the creation time is not known. This is the log processing pipeline’s best effort determination of when the log payload was generated. Add the |
| This is geo-ip of the machine. |
|
The |
| The IP address V4 of the source server, which can be an array. |
| The IP address V6 of the source server, if available. |
|
The logging level as provided by
* You should only use
* Consider
*
* Convert
* Convert
Numeric values from Log levels and priorities from other logging systems should be mapped to the nearest match. See python logging for an example. |
| A typical log entry message, or payload. It can be stripped of metadata pulled out of it by the collector or normalizer, that is UTF-8 encoded. |
| This is the process ID of the logging entity, if available. |
|
The name of the service associated with the logging entity, if available. For example, the |
| Optionally provided operator defined list of tags placed on each log by the collector or normalizer. The payload can be a string with whitespace-delimited string tokens, or a JSON list of string tokens. |
|
Optional path to the file containing the log entry local to the collector |
| The offset value can represent bytes to the start of the log line in the file (zero or one based), or log line numbers (zero or one based), as long as the values are strictly monotonically increasing in the context of a single log file. The values are allowed to wrap, representing a new version of the log file (rotation). |
|
Associate this record with the |
|
This is the |
collectd
Fields
The following fields represent namespace metrics metadata.
Parameter | Description |
---|---|
| type: float
The |
| type: string
The |
| type: string
The |
| type: string
The |
| type: string
The |
| type: string
The |
collectd.processes
Fields
The following field corresponds to the collectd
processes plug-in.
Parameter | Description |
---|---|
|
type: integer The |
collectd.processes.ps_disk_ops
Fields
The collectd
ps_disk_ops
type of processes plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
collectd.processes.ps_cputime
Fields
The collectd
ps_cputime
type of processes plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.processes.ps_count
Fields
The collectd
ps_count
type of processes plug-in.
Parameter | Description |
---|---|
| type: integer
|
| type: integer
|
collectd.processes.ps_pagefaults
Fields
The collectd
ps_pagefaults
type of processes plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.processes.ps_disk_octets
Fields
The collectd ps_disk_octets
type of processes plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
| type: float
The |
collectd.disk
Fields
Corresponds to collectd
disk plug-in.
collectd.disk.disk_merged
Fields
The collectd
disk_merged
type of disk plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.disk.disk_octets
Fields
The collectd
disk_octets
type of disk plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.disk.disk_time
Fields
The collectd
disk_time
type of disk plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.disk.disk_ops
Fields
The collectd
disk_ops
type of disk plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
| type: integer
The |
collectd.disk.disk_io_time
Fields
The collectd disk_io_time
type of disk plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.interface
Fields
Corresponds to the collectd
interface plug-in.
collectd.interface.if_octets
Fields
The collectd
if_octets
type of interface plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.interface.if_packets
Fields
The collectd
if_packets
type of interface plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.interface.if_errors
Fields
The collectd
if_errors
type of interface plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.interface.if_dropped Fields
The collectd
if_dropped
type of interface plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.virt
Fields
Corresponds to collectd
virt plug-in.
collectd.virt.if_octets
Fields
The collectd if_octets
type of virt plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.virt.if_packets
Fields
The collectd
if_packets
type of virt plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.virt.if_errors
Fields
The collectd
if_errors
type of virt plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.virt.if_dropped
Fields
The collectd
if_dropped
type of virt plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.virt.disk_ops
Fields
The collectd
disk_ops
type of virt plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
collectd.virt.disk_octets
Fields
The collectd
disk_octets
type of virt plug-in.
Parameter | Description |
---|---|
| type: float
|
| type: float
|
| type: float
The |
| type: float
The |
| type: float
The |
collectd.CPU
Fields
Corresponds to the collectd
CPU plug-in.
Parameter | Description |
---|---|
| type: float
The |
collectd.df Fields
Corresponds to the collectd
df
plug-in.
Parameter | Description |
---|---|
| type: float
The |
| type: float
The |
collectd.entropy
Fields
Corresponds to the collectd
entropy plug-in.
Parameter | Description |
---|---|
| type: integer
The |
collectd.memory
Fields
Corresponds to the collectd
memory plug-in.
Parameter | Description |
---|---|
| type: float
The |
| type: float
The |
collectd.swap
Fields
Corresponds to the collectd
swap plug-in.
Parameter | Description |
---|---|
| type: integer
The |
| type: integer
The |
collectd.load
Fields
Corresponds to the collectd
load plug-in.
collectd.load.load
Fields
The collectd
load type of load plug-in
Parameter | Description |
---|---|
| type: float
|
| type: float
|
| type: float
|
collectd.aggregation
Fields
Corresponds to collectd
aggregation plug-in.
Parameter | Description |
---|---|
| type: float
|
collectd.statsd
Fields
Corresponds to collectd
statsd
plug-in.
Parameter | Description |
---|---|
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The collectd` |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
collectd.postgresql Fields
Corresponds to collectd
postgresql
plug-in.
Parameter | Description |
---|---|
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
| type: integer
The |
12.2. rsyslog
exported fields
These are the rsyslog
fields exported by the logging system and available for searching from Elasticsearch and Kibana.
The following fields are RFC5424 based metadata.
Parameter | Description |
---|---|
|
See |
|
This is the |
|
See |
|
This is the |
|
If |
12.3. systemd
exported fields
These are the systemd
fields exported by the OpenShift Container Platform cluster logging available for searching from Elasticsearch and Kibana.
Contains common fields specific to systemd
journal. Applications may write their own fields to the journal. These will be available under the systemd.u
namespace. RESULT
and UNIT
are two such fields.
systemd.k
Fields
The following table contains systemd
kernel-specific metadata.
Parameter | Description |
---|---|
|
|
|
|
|
|
|
|
|
|
systemd.t
Fields
systemd.t Fields
are trusted journal fields, fields that are implicitly added by the journal, and cannot be altered by client code.
Parameter | Description |
---|---|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
systemd.u
Fields
systemd.u Fields
are directly passed from clients and stored in the journal.
Parameter | Description |
---|---|
|
|
|
|
|
|
|
|
|
|
| For private use only. |
| For private use only. |
12.4. Kubernetes exported fields
These are the Kubernetes fields exported by the OpenShift Container Platform cluster logging available for searching from Elasticsearch and Kibana.
The namespace for Kubernetes-specific metadata. The kubernetes.pod_name
is the name of the pod.
kubernetes.labels
Fields
Labels attached to the OpenShift object are kubernetes.labels
. Each label name is a subfield of labels field. Each label name is de-dotted, meaning dots in the name are replaced with underscores.
Parameter | Description |
---|---|
| Kubernetes ID of the pod. |
| The name of the namespace in Kubernetes. |
| ID of the namespace in Kubernetes. |
| Kubernetes node name. |
| The name of the container in Kubernetes. |
| The deployment associated with the Kubernetes object. |
| The deploymentconfig associated with the Kubernetes object. |
| The component associated with the Kubernetes object. |
| The provider associated with the Kubernetes object. |
kubernetes.annotations
Fields
Annotations associated with the OpenShift object are kubernetes.annotations
fields.
12.5. Container exported fields
These are the Docker fields exported by the OpenShift Container Platform cluster logging available for searching from Elasticsearch and Kibana. Namespace for docker container-specific metadata. The docker.container_id is the Docker container ID.
pipeline_metadata.collector
Fields
This section contains metadata specific to the collector.
Parameter | Description |
---|---|
| FQDN of the collector. It might be different from the FQDN of the actual emitter of the logs. |
| Name of the collector. |
| Version of the collector. |
| IP address v4 of the collector server, can be an array. |
| IP address v6 of the collector server, can be an array. |
| How the log message was received by the collector whether it was TCP/UDP, or imjournal/imfile. |
| Time when the message was received by the collector. |
| The original non-parsed log message, collected by the collector or as close to the source as possible. |
pipeline_metadata.normalizer
Fields
This section contains metadata specific to the normalizer.
Parameter | Description |
---|---|
| FQDN of the normalizer. |
| Name of the normalizer. |
| Version of the normalizer. |
| IP address v4 of the normalizer server, can be an array. |
| IP address v6 of the normalizer server, can be an array. |
| how the log message was received by the normalizer whether it was TCP/UDP. |
| Time when the message was received by the normalizer. |
| The original non-parsed log message as it is received by the normalizer. |
| The field records the trace of the message. Each collector and normalizer appends information about itself and the date and time when the message was processed. |
12.6. oVirt exported fields
These are the oVirt fields exported by the OpenShift Container Platform cluster logging available for searching from Elasticsearch and Kibana.
Namespace for oVirt metadata.
Parameter | Description |
---|---|
| The type of the data source, hosts, VMS, and engine. |
| The oVirt host UUID. |
ovirt.engine
Fields
Namespace for oVirt engine related metadata. The FQDN of the oVirt engine is ovirt.engine.fqdn
12.7. Aushape exported fields
These are the Aushape fields exported by the OpenShift Container Platform cluster logging available for searching from Elasticsearch and Kibana.
Audit events converted with Aushape. For more information, see Aushape.
Parameter | Description |
---|---|
| Audit event serial number. |
| Name of the host where the audit event occurred. |
| The error aushape encountered while converting the event. |
| An array of JSONPath expressions relative to the event object, specifying objects or arrays with the content removed as the result of event size limiting. An empty string means the event removed the content, and an empty array means the trimming occurred by unspecified objects and arrays. |
| An array log record strings representing the original audit event. |
aushape.data
Fields
Parsed audit event data related to Aushape.
Parameter | Description |
---|---|
| type: nested |
| type: string |
| type: nested |
| type: nested |
| type: nested |
12.8. Tlog exported fields
These are the Tlog fields exported by the OpenShift Container Platform cluster logging system and available for searching from Elasticsearch and Kibana.
Tlog terminal I/O recording messages. For more information see Tlog.
Parameter | Description |
---|---|
| Message format version number. |
| Recorded user name. |
| Terminal type name. |
| Audit session ID of the recorded session. |
| ID of the message within the session. |
| Message position in the session, milliseconds. |
| Distribution of this message’s events in time. |
| Input text with invalid characters scrubbed. |
| Scrubbed invalid input characters as bytes. |
| Output text with invalid characters scrubbed. |
| Scrubbed invalid output characters as bytes. |
Chapter 13. Uninstalling Cluster Logging
You can remove cluster logging from your OpenShift Container Platform cluster.
13.1. Uninstalling cluster logging from OpenShift Container Platform
You can remove cluster logging from your cluster.
Prerequisites
- Cluster logging and Elasticsearch must be installed.
Procedure
To remove cluster logging:
Use the following command to remove everything generated during the deployment.
$ oc delete clusterlogging instance -n openshift-logging