Chapter 2. Master and Node Configuration
2.1. Overview
The openshift start command is used to launch OpenShift servers. The command and its subcommands (master to launch a master server and node to launch a node server) all take a limited set of arguments that are sufficient for launching servers in a development or experimental environment.
However, these arguments are insufficient to describe and control the full set of configuration and security options that are necessary in a production environment. To provide those options, it is necessary to use the dedicated master and node configuration files.
Master configuration files and node configuration files are fully specified with no default values. Therefore, any empty value indicates that you want to start up with an empty value for that parameter. This makes it easy to reason about exactly what your configuration is, but it also makes it difficult to remember all of the options to specify. To make this easier, the configuration files can be created with the --write-config option and then used with the --config option.
2.2. Creating New Configuration Files
For masters, the openshift start command accepts options that indicate that it should simply write the configuration files that it would have used, then terminate. For nodes, a configuration file can be written using the oadm create-node-config command. Creating new configuration files is useful to get a starting point for defining your configuration.
The following commands write the relevant launch configuration file(s), certificate files, and any other necessary files to the specified --write-config or --node-dir directory.
To create configuration files for an all-in-one server (a master and a node on the same host) in the specified directory:
$ openshift start --write-config=/openshift.local.config
To create a master configuration file and other required files in the specified directory:
$ openshift start master --write-config=/openshift.local.config/master
To create a node configuration file and other related files in the specified directory:
$ oadm create-node-config --node-dir=/openshift.local.config/node-<node_hostname> --node=<node_hostname> --hostnames=<hostname>,<ip_address>
For the --hostnames option in the above command, use a comma-delimited list of every host name or IP address you want server certificates to be valid for. The above command also assumes that certificate files are located in an openshift.local.config/master/ directory. If they are not, you can include options to specify their location. Run the command with the -h option to see details.
2.3. Launching Servers Using Configuration Files
Once you have modified the master and/or node configuration files to your specifications, you can use them when launching servers by specifying them as an argument. Keep in mind that if you specify a configuration file, none of the other command line options you pass are respected.
To launch an all-in-one server using a master configuration and a node configuration file:
$ openshift start --master-config=/openshift.local.config/master/master-config.yaml --node-config=/openshift.local.config/node-<node_hostname>/node-config.yaml
To launch a master server using a master configuration file:
$ openshift start master --config=/openshift.local.config/master/master-config.yaml
To launch a node server using a node configuration file:
$ openshift start node --config=/openshift.local.config/node-<node_hostname>/node-config.yaml
2.4. Master Configuration Files
The following master-config.yaml file is a sample master configuration file taken at a point in time. You can create a new master configuration file to see the valid options for your installed version of OpenShift.
Sample Master Configuration File
apiLevels:
- v1beta3
- v1
apiVersion: v1
assetConfig:
logoutURL: ""
masterPublicURL: https://10.0.2.15:8443
publicURL: https://10.0.2.15:8443/console/
servingInfo:
bindAddress: 0.0.0.0:8443
certFile: master.server.crt
clientCA: ""
keyFile: master.server.key
maxRequestsInFlight: 0
requestTimeoutSeconds: 0
controllers: '*'
corsAllowedOrigins:
- 10.0.2.15:8443
- 127.0.0.1
- localhost
dnsConfig:
bindAddress: 0.0.0.0:53
etcdClientInfo:
ca: ca.crt
certFile: master.etcd-client.crt
keyFile: master.etcd-client.key
urls:
- https://10.0.2.15:4001
etcdConfig:
address: 10.0.2.15:4001
peerAddress: 10.0.2.15:7001
peerServingInfo:
bindAddress: 0.0.0.0:7001
certFile: etcd.server.crt
clientCA: ca.crt
keyFile: etcd.server.key
servingInfo:
bindAddress: 0.0.0.0:4001
certFile: etcd.server.crt
clientCA: ca.crt
keyFile: etcd.server.key
storageDirectory: /root/openshift.local.etcd
etcdStorageConfig:
kubernetesStoragePrefix: kubernetes.io
kubernetesStorageVersion: v1
openShiftStoragePrefix: openshift.io
openShiftStorageVersion: v1
imageConfig:
format: openshift/origin-${component}:${version}
latest: false
kind: MasterConfig
kubeletClientInfo:
ca: ca.crt
certFile: master.kubelet-client.crt
keyFile: master.kubelet-client.key
port: 10250
kubernetesMasterConfig:
apiLevels:
- v1beta3
- v1
apiServerArguments: null
controllerArguments: null
masterCount: 1
masterIP: 10.0.2.15
podEvictionTimeout: 5m
schedulerConfigFile: ""
servicesNodePortRange: 30000-32767
servicesSubnet: 172.30.0.0/16
staticNodeNames: []
masterClients:
externalKubernetesKubeConfig: ""
openshiftLoopbackKubeConfig: openshift-master.kubeconfig
masterPublicURL: https://10.0.2.15:8443
networkConfig:
clusterNetworkCIDR: 10.1.0.0/16
hostSubnetLength: 8
networkPluginName: ""
serviceNetworkCIDR: 172.30.0.0/16
oauthConfig:
assetPublicURL: https://10.0.2.15:8443/console/
grantConfig:
method: auto
identityProviders:
- challenge: true
login: true
name: anypassword
provider:
apiVersion: v1
kind: AllowAllPasswordIdentityProvider
masterPublicURL: https://10.0.2.15:8443
masterURL: https://10.0.2.15:8443
sessionConfig:
sessionMaxAgeSeconds: 300
sessionName: ssn
sessionSecretsFile: ""
tokenConfig:
accessTokenMaxAgeSeconds: 86400
authorizeTokenMaxAgeSeconds: 300
policyConfig:
bootstrapPolicyFile: policy.json
openshiftInfrastructureNamespace: openshift-infra
openshiftSharedResourcesNamespace: openshift
projectConfig:
defaultNodeSelector: ""
projectRequestMessage: ""
projectRequestTemplate: ""
securityAllocator:
mcsAllocatorRange: s0:/2
mcsLabelsPerProject: 5
uidAllocatorRange: 1000000000-1999999999/10000
routingConfig:
subdomain: router.default.svc.cluster.local
serviceAccountConfig:
managedNames:
- default
- builder
- deployer
masterCA: ca.crt
privateKeyFile: serviceaccounts.private.key
publicKeyFiles:
- serviceaccounts.public.key
servingInfo:
bindAddress: 0.0.0.0:8443
certFile: master.server.crt
clientCA: ca.crt
keyFile: master.server.key
maxRequestsInFlight: 0
requestTimeoutSeconds: 3600
2.5. Node Configuration Files
The following node-config.yaml file is a sample node configuration file taken at a point in time. You can create a new node configuration file to see the valid options for your installed version of OpenShift.
Example 2.1. Sample Node Configuration File
allowDisabledDocker: true
apiVersion: v1
dnsDomain: cluster.local
dnsIP: 10.0.2.15
dockerConfig:
execHandlerName: native
imageConfig:
format: openshift/origin-${component}:${version}
latest: false
kind: NodeConfig
masterKubeConfig: node.kubeconfig
networkConfig:
mtu: 1450
networkPluginName: ""
nodeIP: ""
nodeName: node1.example.com
podManifestConfig: 1
path: "/path/to/pod-manifest-file" 2
fileCheckIntervalSeconds: 30 3
servingInfo:
bindAddress: 0.0.0.0:10250
certFile: server.crt
clientCA: node-client-ca.crt
keyFile: server.key
volumeDirectory: /root/openshift.local.volumes- 1
- Allows pods to be placed directly on certain set of nodes, or on all nodes without going through the scheduler. You can then use pods to perform the same administrative tasks and support the same services on each node.
- 2
- Specifies the path for the pod manifest file or directory. If it is a directory, then it is expected to contain one or more manifest files. This is used by the Kubelet to create pods on the node.
- 3
- This is the interval (in seconds) for checking the manifest file for new data. The interval must be a positive value.
