Chapter 4. CLI Operations

4.1. Overview

This topic provides information on the CLI operations and their syntax. You must setup and login with the CLI before you can perform these operations.

4.2. Common Operations

The CLI allows interaction with the various objects that are managed by OpenShift. Many common oc operations are invoked using the following syntax: 

$ oc <action> <object_type> <object_name_or_id>

This specifies:

  • An <action> to perform, such as get or describe.
  • The <object_type> to perform the action on, such as service or the abbreviated svc.
  • The <object_name_or_id> of the specified <object_type>.

For example, the oc get operation returns a complete list of services that are currently defined: 

$ oc get svc
NAME              LABELS                                    SELECTOR                  IP              PORT(S)
docker-registry   docker-registry=default                   docker-registry=default   172.30.78.158   5000/TCP
kubernetes        component=apiserver,provider=kubernetes   <none>                    172.30.0.2      443/TCP
kubernetes-ro     component=apiserver,provider=kubernetes   <none>                    172.30.0.1      80/TCP

The oc describe operation can then be used to return detailed information about a specific object: 

$ oc describe svc docker-registry
Name:			docker-registry
Labels:			docker-registry=default
Selector:		docker-registry=default
IP:			172.30.78.158
Port:			<unnamed>	5000/TCP
Endpoints:		10.1.0.2:5000
Session Affinity:	None
No events.
Warning

Versions of oc prior to 3.0.2.0 did not have the ability to negotiate API versions against a server. So if you are using oc up to 3.0.1.0 with a server that only supports v1 or higher versions of the API, make sure to pass --api-version in order to point the oc client to the correct API endpoint. For example: oc get svc --api-version=v1.

4.3. Basic CLI Operations

The following table describes basic oc operations and their general syntax:

OperationSyntaxDescription

types

oc types

Display an introduction to some core OpenShift concepts.

login

oc login

Log in to the OpenShift server.

logout

oc logout

End the current session.

new-project

oc new-project <project_name>

Create a new project.

new-app

oc new-app .

Creates a new application based on the source code in the current directory.

status

oc status

Show an overview of the current project.

project

oc project <project_name>

Switch to another project. Run without options to display the current project. To view all projects you have access to run oc projects.

4.4. Application Modification CLI Operations

OperationSyntaxDescription

get

oc get <object_type> [<object_name_or_id>]

Return a list of objects for the specified object type. If the optional <object_name_or_id> is included in the request, then the list of results is filtered by that value.

describe

oc describe <object_type> <object_id>

Returns information about the specific object returned by the query. A specific <object_name_or_id> must be provided. The actual information that is available varies as described in object type.

edit

oc edit <object_type>/<object_type_name>

Edit the desired object type.

OC_EDITOR="<text_editor>" oc edit \<object_type>/<object_type_name>

Edit the desired object type with a specified text editor.

oc edit <object_type>/<object_type_name> \--output-version=<object_type_version> \-o <object_type_format>

Edit the desired object in a specified format (eg: JSON).

env

oc env <object_type>/<object_type_name> \<EN_VAR>=/<VALUE>

Update the desired object type with a new environment variable

volume

oc volume <object_type>/<object_type_name> \[--option]

Modify a volume.

label

oc label <object_type> <object_name_or_id> \<label>

Update the labels on a object.

expose

oc expose <object_type> <object_name_or_id>

Look up a service and expose it as a route. There is also the ability to expose a deployment configuration, replication controller, service, or pod as a new service on a specified port. If no labels are specified, the new object will re-use the labels from the object it exposes.

stop

oc stop -f <file_path>

Gracefully shut down an object by ID or file name. Attempt to shut down and delete an object that supports graceful termination.

oc stop <object_type> <object_name_or_id>

Gracefully shut down an object with the specified ID.

oc stop <object_type> -l <label>

Gracefully shut down an object with the specified label.

oc stop all -l <label>

Gracefully shut down all objects with the specified label.

delete

oc delete -f <file_path>

oc delete <object_type> <object_name_or_id>

oc delete <object_type> -l <label>

oc delete all -l <label>

Delete the specified object. An object configuration can also be passed in through STDIN. The oc delete all -l <label> operation deletes all objects matching the specified <label>, including the replication controller so that pods are not re-created.

4.5. Build and Deployment CLI Operations

One of the fundamental capabilities of OpenShift is the ability to build applications into a container from source. The following table describes the CLI operations for working with application builds:

OpenShift provides CLI access to inspect and manipulate deployment configurations using standard oc resource operations, such as get, create, and describe.

OperationSyntaxDescription

start-build

oc start-build <buildConfig_name>

Manually start the build process with the specified build configuration file.

oc start-build --from-build=<build_name>

Manually start the build process by specifying the name of a previous build as a starting point.

oc start-build \<buildConfig_name> --follow

oc start-build \--from-build=<build_name> --follow

Manually start the build process by specifying either a configuration file or the name of a previous build and retrieves its build logs.

build-logs

oc build-logs <build_name>

Retrieve the build logs for the specified build.

deploy

oc deploy <deploymentconfig>

View a deployment, or manually start, cancel, or retry a deployment.

rollback

oc rollback <deployment_name>

Perform a rollback.

new-build

oc new-build .

Create a build config based on the source code in the current git repository (with a public remote) and a Docker image

cancel-build

oc cancel-build <build_name>

Stop a build that is in progress.

import-image

oc import-image <imagestream>

Import tag and image information from an external Docker image repository.

scale

oc scale <object_type> <object_id> \--replicas=<#_of_replicas>

Set the number of desired replicas for a replication controller or a deployment configuration to the number of specified replicas.

tag

oc tag <current_image> <image_stream>

Take an existing tag or image from an image stream, or a Docker image pull spec, and set it as the most recent image for a tag in one or more other image streams.

4.6. Advanced Commands

OperationSyntaxDescription

create

oc create -f <file_or_dir_path>

Parse a configuration file and create one or more OpenShift objects based on the file contents. The -f flag can be passed multiple times with different file or directory paths. When the flag is passed multiple times, oc create iterates through each one, creating the objects described in all of the indicated files. Any existing resources are ignored.

update

oc update -f <file_or_dir_path>

Attempt to modify an existing object based on the contents of the specified configuration file. The -f flag can be passed multiple times with different file or directory paths. When the flag is passed multiple times, oc update iterates through each one, updating the objects described in all of the indicated files.

process

oc process -f <template_file_path>

Transform a project template into a project configuration file.

export

oc export <object_type> [--options]

Export resources to be used elsewhere

policy

oc policy [--options]

Manage authorization policies

secrets

oc secrets [--options] path/to/ssh_key

Configure secrets.

4.7. Troubleshooting and Debugging CLI Operations

OperationSyntaxDescription

logs

oc logs -f <pod_name> <container_name>

Retrieve the log output for a specific pod or container. This command does not work for other object types.

exec

oc exec <pod_ID> \[-c <container_ID>] <command>

Execute a command in an already-running container. You can optionally specify a container ID, otherwise it defaults to the first container.

rsh

oc rsh <pod_ID>

Open a remote shell session to a container.

port-forward

oc port-forward <pod_ID> \<first_port_ID> <second_port_ID>

Forward one or more local ports to a pod.

proxy

oc proxy --port=<port_ID> \--www=<static_directory>

Run a proxy to the Kubernetes API server

Important

For security purposes, the oc exec command does not work when accessing privileged containers. Instead, administrators can SSH into a node host, then use the docker exec command on the desired container.

4.8. Object Types

The CLI supports the following object types, some of which have abbreviated syntax:

Object TypeAbbreviated Version

build

 

buildConfig

bc

deploymentConfig

dc

imageStream

is

imageStreamTag

istag

imageStreamImage

isimage

event

ev

node

 

pod

po

replicationController

rc

service

svc

persistentVolume

pv

persistentVolumeClaim

pvc