OpenShift for Developers

Chapter 8. Working with Your Application

Applications are great when they are working properly, but inevitably at some point most applications will need to be debugged. You might also need to tweak your application’s build, or see what resources it has available. In this chapter we will dig into various tasks related to working with your application, whether as developer or as part of an operations team. While we have focused on using the OpenShift web console so far, in this chapter, we use the command-line tools so you can become more familiar with them.

Listing Running Instances

Information about running instances of your application can be found on the Pods page of the OpenShift web console.

If you want to find out what instances are running from the command line, you can use the oc get pods command:

$ oc get pods
NAME                    READY     STATUS      RESTARTS   AGE
helloworld-1-build      0/1       Completed   0          37m
helloworld-2-build      0/1       Completed   0          33m
helloworld-3-build      0/1       Completed   0          28m
helloworld-4-build      0/1       Completed   0          11m
helloworld-4-cd3y3      1/1       Running     0          9m

In this list, it is the pods with the Running status that are the instances of your application.

You can get a wealth of information about a specific instance using the oc describe command:

$ oc describe pod/helloworld-4-cd3y3 Name: helloworld-4-cd3y3 Namespace: wfproject Image(s): 172.30.210.155:5000/wfproject/helloworld@sha256:9c941cb... Node: origin/10.0.2.15 Start Time: Thu, 17 Mar 2016 11:30:08 +1100 Labels: app=helloworld,deployment=helloworld-4,deploymentconfig=helloworld ...