OpenShift Pod Operations

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List Pods for a Project

oc get projects

oc get -n <project-name> pods

List Pods on Nodes

oadm manage-node <node-name> --list-pods

Pod Status

The most complete information set is generated by "oc get -o yaml pod ..." and "oc describe pod ...":

oc [-n <project-name>] [[oc get#pods|get pods]
oc [-n <project-name>] -o yaml get pod] <pod-name>
oc [-n <project-name>] describe pod <pod-name>
oc [-n <project-name>] describe pod/<pod-name>
oc [-n <project-name>] edit pod/<pod-name>

Monitor Pod's Logs

oc logs -f <pod-name>

Execute Commands in Containers

oc rsh <pod-id> <command>

Deploy a Simple Pod that Allows Arbitrary Commands in a Project

Simple Pod Running inside an OpenShift Project

Update a Pod Defintion

Stopping Pods

A pod can be stopped by deleting its associated "pod" object:

oc delete pod/logging-fluentd-3kz30

The controller (either replication or DamonSet) will detect that the pod is missing and it will start a new one.

Evacuate Pods from Node

Only pods backed by replication controllers can be evacuated. The "bare" pods cannot be evacuated.

Drain the node.

oadm drain <node-name> [--delete-local-data] [--ignore-daemonsets] [--force] 
oadm drain node2 --delete-local-data --ignore-daemonsets

Use --delete-local-data if there are pods with local storage - such as Maven build pods.

Use --ignore-daemonset if there are ignore DaemonSets: If there are DaemonSet-managed pods, drain will not proceed without --ignore-daemonsets, and regardless it will not delete any DaemonSet-managed pods, because those pods would be immediately replaced by the DaemonSet controller, which ignores unschedulable markings.

oadm manage-node --evacuate is deprecated.

Scaling Down and Up the Number of Replicas associated with a DeploymentConfig

Application Operations - Scaling Up and Down the Number of Replicas associated with a DeploymentConfig