第 5 章 操作节点
5.1. 查看和列出 OpenShift Container Platform 集群中的节点
您可以列出集群中的所有节点，以获取节点的相关信息，如状态、年龄、内存用量和其他详情。
在执行节点管理操作时，CLI 与代表实际节点主机的节点对象交互。主控机（master）使用来自节点对象的信息执行健康检查，以此验证节点。
5.1.1. 关于列出集群中的所有节点
您可以获取集群中节点的详细信息。
以下命令列出所有节点：
$ oc get nodes
以下示例是具有健康节点的集群：
$ oc get nodes
输出示例
NAME STATUS ROLES AGE VERSION master.example.com Ready master 7h v1.21.0 node1.example.com Ready worker 7h v1.21.0 node2.example.com Ready worker 7h v1.21.0
以下示例是具有一个不健康节点的集群：
$ oc get nodes
输出示例
NAME STATUS ROLES AGE VERSION master.example.com Ready master 7h v1.21.0 node1.example.com NotReady,SchedulingDisabled worker 7h v1.21.0 node2.example.com Ready worker 7h v1.21.0
触发
NotReady状态的条件在本节中显示。-o wide选项提供有关节点的附加信息。$ oc get nodes -o wide
输出示例
NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME master.example.com Ready master 171m v1.21.0+39c0afe 10.0.129.108 <none> Red Hat Enterprise Linux CoreOS 48.83.202103210901-0 (Ootpa) 4.18.0-240.15.1.el8_3.x86_64 cri-o://1.21.0-30.rhaos4.8.gitf2f339d.el8-dev node1.example.com Ready worker 72m v1.21.0+39c0afe 10.0.129.222 <none> Red Hat Enterprise Linux CoreOS 48.83.202103210901-0 (Ootpa) 4.18.0-240.15.1.el8_3.x86_64 cri-o://1.21.0-30.rhaos4.8.gitf2f339d.el8-dev node2.example.com Ready worker 164m v1.21.0+39c0afe 10.0.142.150 <none> Red Hat Enterprise Linux CoreOS 48.83.202103210901-0 (Ootpa) 4.18.0-240.15.1.el8_3.x86_64 cri-o://1.21.0-30.rhaos4.8.gitf2f339d.el8-dev
以下命令列出一个节点的相关信息：
$ oc get node <node>
例如：
$ oc get node node1.example.com
输出示例
NAME STATUS ROLES AGE VERSION node1.example.com Ready worker 7h v1.21.0
以下命令提供有关特定节点的更多详细信息，包括发生当前状况的原因：
$ oc describe node <node>
例如：
$ oc describe node node1.example.com
输出示例
Name: node1.example.com 1 Roles: worker 2 Labels: beta.kubernetes.io/arch=amd64 3 beta.kubernetes.io/instance-type=m4.large beta.kubernetes.io/os=linux failure-domain.beta.kubernetes.io/region=us-east-2 failure-domain.beta.kubernetes.io/zone=us-east-2a kubernetes.io/hostname=ip-10-0-140-16 node-role.kubernetes.io/worker= Annotations: cluster.k8s.io/machine: openshift-machine-api/ahardin-worker-us-east-2a-q5dzc 4 machineconfiguration.openshift.io/currentConfig: worker-309c228e8b3a92e2235edd544c62fea8 machineconfiguration.openshift.io/desiredConfig: worker-309c228e8b3a92e2235edd544c62fea8 machineconfiguration.openshift.io/state: Done volumes.kubernetes.io/controller-managed-attach-detach: true CreationTimestamp: Wed, 13 Feb 2019 11:05:57 -0500 Taints: <none> 5 Unschedulable: false Conditions: 6 Type Status LastHeartbeatTime LastTransitionTime Reason Message ---- ------ ----------------- ------------------ ------ ------- OutOfDisk False Wed, 13 Feb 2019 15:09:42 -0500 Wed, 13 Feb 2019 11:05:57 -0500 KubeletHasSufficientDisk kubelet has sufficient disk space available MemoryPressure False Wed, 13 Feb 2019 15:09:42 -0500 Wed, 13 Feb 2019 11:05:57 -0500 KubeletHasSufficientMemory kubelet has sufficient memory available DiskPressure False Wed, 13 Feb 2019 15:09:42 -0500 Wed, 13 Feb 2019 11:05:57 -0500 KubeletHasNoDiskPressure kubelet has no disk pressure PIDPressure False Wed, 13 Feb 2019 15:09:42 -0500 Wed, 13 Feb 2019 11:05:57 -0500 KubeletHasSufficientPID kubelet has sufficient PID available Ready True Wed, 13 Feb 2019 15:09:42 -0500 Wed, 13 Feb 2019 11:07:09 -0500 KubeletReady kubelet is posting ready status Addresses: 7 InternalIP: 10.0.140.16 InternalDNS: ip-10-0-140-16.us-east-2.compute.internal Hostname: ip-10-0-140-16.us-east-2.compute.internal Capacity: 8 attachable-volumes-aws-ebs: 39 cpu: 2 hugepages-1Gi: 0 hugepages-2Mi: 0 memory: 8172516Ki pods: 250 Allocatable: attachable-volumes-aws-ebs: 39 cpu: 1500m hugepages-1Gi: 0 hugepages-2Mi: 0 memory: 7558116Ki pods: 250 System Info: 9 Machine ID: 63787c9534c24fde9a0cde35c13f1f66 System UUID: EC22BF97-A006-4A58-6AF8-0A38DEEA122A Boot ID: f24ad37d-2594-46b4-8830-7f7555918325 Kernel Version: 3.10.0-957.5.1.el7.x86_64 OS Image: Red Hat Enterprise Linux CoreOS 410.8.20190520.0 (Ootpa) Operating System: linux Architecture: amd64 Container Runtime Version: cri-o://1.16.0-0.6.dev.rhaos4.3.git9ad059b.el8-rc2 Kubelet Version: v1.21.0 Kube-Proxy Version: v1.21.0 PodCIDR: 10.128.4.0/24 ProviderID: aws:///us-east-2a/i-04e87b31dc6b3e171 Non-terminated Pods: (13 in total) 10 Namespace Name CPU Requests CPU Limits Memory Requests Memory Limits --------- ---- ------------ ---------- --------------- ------------- openshift-cluster-node-tuning-operator tuned-hdl5q 0 (0%) 0 (0%) 0 (0%) 0 (0%) openshift-dns dns-default-l69zr 0 (0%) 0 (0%) 0 (0%) 0 (0%) openshift-image-registry node-ca-9hmcg 0 (0%) 0 (0%) 0 (0%) 0 (0%) openshift-ingress router-default-76455c45c-c5ptv 0 (0%) 0 (0%) 0 (0%) 0 (0%) openshift-machine-config-operator machine-config-daemon-cvqw9 20m (1%) 0 (0%) 50Mi (0%) 0 (0%) openshift-marketplace community-operators-f67fh 0 (0%) 0 (0%) 0 (0%) 0 (0%) openshift-monitoring alertmanager-main-0 50m (3%) 50m (3%) 210Mi (2%) 10Mi (0%) openshift-monitoring grafana-78765ddcc7-hnjmm 100m (6%) 200m (13%) 100Mi (1%) 200Mi (2%) openshift-monitoring node-exporter-l7q8d 10m (0%) 20m (1%) 20Mi (0%) 40Mi (0%) openshift-monitoring prometheus-adapter-75d769c874-hvb85 0 (0%) 0 (0%) 0 (0%) 0 (0%) openshift-multus multus-kw8w5 0 (0%) 0 (0%) 0 (0%) 0 (0%) openshift-sdn ovs-t4dsn 100m (6%) 0 (0%) 300Mi (4%) 0 (0%) openshift-sdn sdn-g79hg 100m (6%) 0 (0%) 200Mi (2%) 0 (0%) Allocated resources: (Total limits may be over 100 percent, i.e., overcommitted.) Resource Requests Limits -------- -------- ------ cpu 380m (25%) 270m (18%) memory 880Mi (11%) 250Mi (3%) attachable-volumes-aws-ebs 0 0 Events: 11 Type Reason Age From Message ---- ------ ---- ---- ------- Normal NodeHasSufficientPID 6d (x5 over 6d) kubelet, m01.example.com Node m01.example.com status is now: NodeHasSufficientPID Normal NodeAllocatableEnforced 6d kubelet, m01.example.com Updated Node Allocatable limit across pods Normal NodeHasSufficientMemory 6d (x6 over 6d) kubelet, m01.example.com Node m01.example.com status is now: NodeHasSufficientMemory Normal NodeHasNoDiskPressure 6d (x6 over 6d) kubelet, m01.example.com Node m01.example.com status is now: NodeHasNoDiskPressure Normal NodeHasSufficientDisk 6d (x6 over 6d) kubelet, m01.example.com Node m01.example.com status is now: NodeHasSufficientDisk Normal NodeHasSufficientPID 6d kubelet, m01.example.com Node m01.example.com status is now: NodeHasSufficientPID Normal Starting 6d kubelet, m01.example.com Starting kubelet. ...
在显示的节点信息中，本节显示的命令输出中会出现以下节点状况：
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5.1.2. 列出集群中某一节点上的 pod
您可以列出特定节点上的所有 pod。
流程
列出一个或多个节点上的所有或选定 pod：
$ oc describe node <node1> <node2>
例如：
$ oc describe node ip-10-0-128-218.ec2.internal
列出选定节点上的所有或选定 pod：
$ oc describe --selector=<node_selector>
$ oc describe node --selector=kubernetes.io/os
或者：
$ oc describe -l=<pod_selector>
$ oc describe node -l node-role.kubernetes.io/worker
列出特定节点上的所有 pod，包括终止的 pod：
$ oc get pod --all-namespaces --field-selector=spec.nodeName=<nodename>
5.1.3. 查看节点上的内存和 CPU 用量统计
您可以显示节点的用量统计，这些统计信息为容器提供了运行时环境。这些用量统计包括 CPU、内存和存储的消耗。
先决条件
-
您必须有
cluster-reader权限才能查看用量统计。 - 必须安装 Metrics 才能查看用量统计。
流程
查看用量统计：
$ oc adm top nodes
输出示例
NAME CPU(cores) CPU% MEMORY(bytes) MEMORY% ip-10-0-12-143.ec2.compute.internal 1503m 100% 4533Mi 61% ip-10-0-132-16.ec2.compute.internal 76m 5% 1391Mi 18% ip-10-0-140-137.ec2.compute.internal 398m 26% 2473Mi 33% ip-10-0-142-44.ec2.compute.internal 656m 43% 6119Mi 82% ip-10-0-146-165.ec2.compute.internal 188m 12% 3367Mi 45% ip-10-0-19-62.ec2.compute.internal 896m 59% 5754Mi 77% ip-10-0-44-193.ec2.compute.internal 632m 42% 5349Mi 72%
查看具有标签的节点的用量统计信息：
$ oc adm top node --selector=''
您必须选择过滤所基于的选择器（标签查询）。支持
=、==和!=。
