Viewing pods

As an administrator, you can view the pods in your cluster and to determine the health of those pods and the cluster as a whole.

About pods

OKD leverages the Kubernetes concept of a pod, which is one or more containers deployed together on one host, and the smallest compute unit that can be defined, deployed, and managed. Pods are the rough equivalent of a machine instance (physical or virtual) to a container.

You can view a list of pods associated with a specific project or view usage statistics about pods.

Viewing pods in a project

You can view a list of pods associated with the current project, including the number of replica, the current status, number or restarts and the age of the pod.

Procedure

To view the pods in a project:

1. Change to the project:

   $ oc project <project-name>

2. Run the following command:

   $ oc get pods

   For example:

   $ oc get pods -n openshift-console

   Example output

   NAME                       READY   STATUS    RESTARTS   AGE
   console-698d866b78-bnshf   1/1     Running   2          165m
   console-698d866b78-m87pm   1/1     Running   2          165m

   Add the -o wide flags to view the pod IP address and the node where the pod is located.

   $ oc get pods -o wide

   Example output

   NAME                       READY   STATUS    RESTARTS   AGE    IP            NODE                           NOMINATED NODE
   console-698d866b78-bnshf   1/1     Running   2          166m   10.128.0.24   ip-10-0-152-71.ec2.internal    <none>
   console-698d866b78-m87pm   1/1     Running   2          166m   10.129.0.23   ip-10-0-173-237.ec2.internal   <none>

Viewing pod usage statistics

You can display usage statistics about pods, which provide the runtime environments for containers. These usage statistics include CPU, memory, and storage consumption.

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:

1. Run the following command:

   $ oc adm top pods

   For example:

   $ oc adm top pods -n openshift-console

   Example output

   NAME                         CPU(cores)   MEMORY(bytes)
   console-7f58c69899-q8c8k     0m           22Mi
   console-7f58c69899-xhbgg     0m           25Mi
   downloads-594fcccf94-bcxk8   3m           18Mi
   downloads-594fcccf94-kv4p6   2m           15Mi

2. Run the following command to view the usage statistics for pods with labels:

   $ oc adm top pod --selector=''

   You must choose the selector (label query) to filter on. Supports =, ==, and !=.

Viewing resource logs

You can view the log for various resources in the OpenShift CLI (oc) and web console. Logs read from the tail, or end, of the log.

Prerequisites

• Access to the OpenShift CLI (oc).

Procedure (UI)

1. In the OKD console, navigate to Workloads → Pods or navigate to the pod through the resource you want to investigate.

   Some resources, such as builds, do not have pods to query directly. In such instances, you can locate the Logs link on the Details page for the resource.

2. Select a project from the drop-down menu.

3. Click the name of the pod you want to investigate.

4. Click Logs.

Procedure (CLI)

• View the log for a specific pod:

  $ oc logs -f <pod_name> -c <container_name>

  where:

  -f

  Optional: Specifies that the output follows what is being written into the logs.

  <pod_name>

  Specifies the name of the pod.

  <container_name>

  Optional: Specifies the name of a container. When a pod has more than one container, you must specify the container name.

  For example:

  $ oc logs ruby-58cd97df55-mww7r

  $ oc logs -f ruby-57f7f4855b-znl92 -c ruby

  The contents of log files are printed out.

• View the log for a specific resource:

  $ oc logs <object_type>/<resource_name> (1)

  1	Specifies the resource type and name.

  For example:

  $ oc logs deployment/ruby

  The contents of log files are printed out.