Chapter 2. Get Started with the CLI

The OpenShift CLI exposes commands for managing your applications, as well as lower level tools to interact with each component of your system. This topic guides you through getting started with the CLI, including installation and logging in to create your first project.

Certain operations require Git to be locally installed on a client. For example, the command to create an application using a remote Git repository:

$ oc new-app https://github.com/<your_user>/<your_git_repo>

Before proceeding, install Git on your workstation. See the official Git documentation for instructions per your workstation’s operating system.

You can download and unpack the CLI from the Red Hat Customer Portal for use on Linux, MacOSX, and Windows clients. After logging in with your Red Hat account, you must have an active OpenShift Enterprise subscription to access the downloads page.

Download the CLI

The oc login command is the best way to initially set up the OpenShift CLI, and it serves as the entry point for most users. The interactive flow helps you establish a session to an OpenShift server with the provided credentials. The information is automatically saved in a CLI configuration file that is then used for subsequent commands.

The following example shows the interactive setup and login using the oc login command:

$ oc login
OpenShift server [https://localhost:8443]: https://openshift.example.com 1

Username: alice 2
Authentication required for https://openshift.example.com (openshift)
Password: ******
Login successful. 3

You don't have any projects. You can try to create a new project, by running

    $ oc new-project <projectname> 4

Welcome to OpenShift! See 'oc help' to get started.

When you have completed the CLI configuration, subsequent commands use the configuration file for the server, session token, and project information.

You can log out of CLI using the oc logout command:

$ oc logout
User, alice, logged out of https://openshift.example.com

If you log in after creating or being granted access to a project, a project you have access to is automatically set as the current default, until switching to another one:

$ oc login
Username: alice
Authentication required for https://openshift.example.com (openshift)
Password:
Login successful.

Using project "aliceproject".

Additional options are also available for the oc login command.

$ oc login -u system:admin -n default

A CLI configuration file permanently stores oc options and contains a series of authentication mechanisms and OpenShift server connection information associated with nicknames.

As described in the previous section, the oc login command automatically creates and manages CLI configuration files. All information gathered by the command is stored in a configuration file located in ~/.kube/config. The current CLI configuration can be viewed using the following command:

$ oc config view
apiVersion: v1
clusters:
- cluster:
    server: https://openshift.example.com
  name: openshift
contexts:
- context:
    cluster: openshift
    namespace: aliceproject
    user: alice
  name: alice
current-context: alice
kind: Config
preferences: {}
users:
- name: alice
  user:
    token: NDM2N2MwODgtNjI1Yy10N3VhLTg1YmItYzI4NDEzZDUyYzVi

CLI configuration files can be used to setup multiple CLI profiles using various OpenShift servers, namespaces, and users so that you can switch easily between them. The CLI can support multiple configuration files; they are loaded at runtime and merged together along with any override options specified from the command line.

A project in OpenShift contains multiple objects to make up a logical "application".

Most oc commands run in the context of a project. The oc login selects a default project during initial setup to be used with subsequent commands. Use the following command to display the project currently in use:

$ oc project

If you have access to multiple projects, use the following syntax to switch to a particular project by specifying the project name:

$ oc project <project_name>

For example:

$ oc project project02
Now using project 'project02'.

$ oc project project03
Now using project 'project03'.

$ oc project
Using project 'project03'.

The oc status command shows a high level overview of the project currently in use, with its components and their relationships, as shown in the following example:

$ oc status
In project OpenShift 3 Sample (test)

service database-test (172.30.17.113:6434 -> 3306)
  database-test deploys docker.io/library/mysql:latest
    #1 deployed 47 hours ago

service frontend-test (172.30.17.236:5432 -> 8080)
  frontend-test deploys origin-ruby-sample:test <-
    builds https://github.com/openshift/ruby-hello-world with docker.io/openshift/ruby-20-centos7:latest
    not built yet
    #1 deployment waiting on image

To see more information about a service or deployment config, use 'oc describe service <name>' or 'oc describe dc <name>'.
You can use 'oc get pods,svc,dc,bc,builds' to see lists of each of the types described above.

After you have logged in, you can create a new application and explore some common CLI operations.