--- title: Viewing and listing the nodes in your OpenShift Container Platform cluster --- # Viewing and listing the nodes in your OpenShift Container Platform cluster {#nodes-nodes-viewing} You can list all the nodes in your cluster to obtain information such as status, age, memory usage, and details about the nodes. When you perform node management operations, the CLI interacts with node objects that are representations of actual node hosts. The master uses the information from node objects to validate nodes with health checks. ## About listing all the nodes in a cluster {#nodes-nodes-viewing-listing_nodes-nodes-viewing} You can get detailed information about the nodes in the cluster, which can help you understand the state of the nodes in your cluster. - The following command lists all nodes: ```terminal $ oc get nodes ``` The following example is a cluster with healthy nodes: ```terminal $ oc get nodes ``` ```terminal {title="Example output"} NAME STATUS ROLES AGE VERSION master.example.com Ready master 7h v1.35.4 node1.example.com Ready worker 7h v1.35.4 node2.example.com Ready worker 7h v1.35.4 ``` The following example is a cluster with one unhealthy node: ```terminal $ oc get nodes ``` ```terminal {title="Example output"} NAME STATUS ROLES AGE VERSION master.example.com Ready master 7h v1.35.4 node1.example.com NotReady,SchedulingDisabled worker 7h v1.35.4 node2.example.com Ready worker 7h v1.35.4 ``` The conditions that trigger a `NotReady` status are shown later in this section. - The `-o wide` option provides additional information on nodes. ```terminal $ oc get nodes -o wide ``` ```terminal {title="Example output"} NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME master.example.com Ready master 171m v1.35.4 10.0.129.108 Red Hat Enterprise Linux CoreOS 48.83.202103210901-0 (Ootpa) 4.22.0-240.15.1.el8_3.x86_64 cri-o://1.35.4-30.rhaos4.10.gitf2f339d.el8-dev node1.example.com Ready worker 72m v1.35.4 10.0.129.222 Red Hat Enterprise Linux CoreOS 48.83.202103210901-0 (Ootpa) 4.22.0-240.15.1.el8_3.x86_64 cri-o://1.35.4-30.rhaos4.10.gitf2f339d.el8-dev node2.example.com Ready worker 164m v1.35.4 10.0.142.150 Red Hat Enterprise Linux CoreOS 48.83.202103210901-0 (Ootpa) 4.22.0-240.15.1.el8_3.x86_64 cri-o://1.35.4-30.rhaos4.10.gitf2f339d.el8-dev ``` - The following command lists information about a single node: ```terminal $ oc get node ``` For example: ```terminal $ oc get node node1.example.com ``` ```terminal {title="Example output"} NAME STATUS ROLES AGE VERSION node1.example.com Ready worker 7h v1.35.4 ``` - The following command provides more detailed information about a specific node, including the reason for the current condition: ```terminal $ oc describe node ``` For example: ```terminal $ oc describe node node1.example.com ``` > [!NOTE] > The following example contains some values that are specific to OpenShift Container Platform on AWS. ```text {title="Example output"} Name: node1.example.com Roles: worker Labels: kubernetes.io/os=linux kubernetes.io/hostname=ip-10-0-131-14 kubernetes.io/arch=amd64 node-role.kubernetes.io/worker= node.kubernetes.io/instance-type=m4.large node.openshift.io/os_id=rhcos node.openshift.io/os_version=4.5 region=east topology.kubernetes.io/region=us-east-1 topology.kubernetes.io/zone=us-east-1a Annotations: cluster.k8s.io/machine: openshift-machine-api/ahardin-worker-us-east-2a-q5dzc 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: Unschedulable: false Conditions: 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: 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: 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: 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://1.35.4-0.6.dev.rhaos4.3.git9ad059b.el8-rc2 Kubelet Version: v1.35.4 Kube-Proxy Version: v1.35.4 PodCIDR: 10.128.4.0/24 ProviderID: aws:///us-east-2a/i-04e87b31dc6b3e171 Non-terminated Pods: (12 in total) 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 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-ovn-kubernetes ovnkube-node-t4dsn 80m (0%) 0 (0%) 1630Mi (0%) 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: 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. #... ``` where: `Names` : Specifies the name of the node. `Roles` : Specifies the role of the node, either `master` or `worker`. `Labels` : Specifies the labels applied to the node. `Annotations` : Specifies the annotations applied to the node. `Taints` : Specifies the taints applied to the node. `Conditions` : Specifies the node conditions and status. The `conditions` stanza lists the `Ready`, `PIDPressure`, `MemoryPressure`, `DiskPressure` and `OutOfDisk` status. These condition are described later in this section. `Addresses` : Specifies the IP address and hostname of the node. `Capacity` : Specifies the pod resources and allocatable resources. `Information` : Specifies information about the node host. `Non-terminated Pods` : Specifies the pods on the node. `Events` : Specifies the events reported by the node. > [!NOTE] > The control plane label is not automatically added to newly created or updated master nodes. If you want to use the control plane label for your nodes, you can manually configure the label. For more information, see "Understanding how to update labels on nodes". Among the information shown for nodes, the following node conditions appear in the output of the commands shown in this section: **Node Conditions**
Condition Description
Ready If true, the node is healthy and ready to accept pods. If false, the node is not healthy and is not accepting pods. If unknown, the node controller has not received a heartbeat from the node for the node-monitor-grace-period (the default is 40 seconds).
DiskPressure If true, the disk capacity is low.
MemoryPressure If true, the node memory is low.
PIDPressure If true, there are too many processes on the node.
OutOfDisk If true, the node has insufficient free space on the node for adding new pods.
NetworkUnavailable If true, the network for the node is not correctly configured.
NotReady If true, one of the underlying components, such as the container runtime or network, is experiencing issues or is not yet configured.
SchedulingDisabled Pods cannot be scheduled for placement on the node.
## Listing pods on a node in your cluster {#nodes-nodes-viewing-listing-pods_nodes-nodes-viewing} You can list all of the pods on a node by using the `oc get pods` command along with specific flags. This command shows the number of pods on that node, the state of the pods, number of pod restarts, and the age of the pods. **Procedure** - To list all or selected pods on selected nodes: ```terminal $ oc get pod --selector= ``` ```terminal $ oc get pod --selector=kubernetes.io/os ``` Or: ```terminal $ oc get pod -l= ``` ```terminal $ oc get pod -l kubernetes.io/os=linux ``` - To list all pods on a specific node, including terminated pods: ```terminal $ oc get pod --all-namespaces --field-selector=spec.nodeName= ``` ## Viewing memory and CPU usage statistics on your nodes {#nodes-nodes-viewing-memory_nodes-nodes-viewing} You can display usage statistics about nodes, including CPU, memory, and storage consumption. These statistics can help you ensure your cluster is running efficiently. **Prerequisites** - You must have `cluster-reader` permission to view the usage statistics. - Metrics must be installed to view the usage statistics. **Procedure** - To view the usage statistics: ```terminal $ oc adm top nodes ``` ```terminal {title="Example output"} 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% ``` - To view the usage statistics for nodes with labels: ```terminal $ oc adm top node --selector='' ``` You must choose the selector (label query) to filter on. Supports `=`, `==`, and `!=`. **Additional resources** {._additional-resources} - [Understanding how to update labels on nodes](/openshift-docs-markdown/nodes/nodes/nodes-nodes-working#nodes-nodes-working-updating_nodes-nodes-working)