Get Application Logs from the Kubernetes Cluster

You can get logs for your application from pods within the Kubernetes cluster.

1. Open a command-line window.
2. Locate the pods for your application. Replace the <app-name> placeholder.

   kubectl get pods | grep "<app-name>"

   Example:

   $ kubectl get pods | grep "webapp01"
   webapp01-deployment-84b7b6b5d4-5lnhb   1/1     Running   0        10d
   webapp01-deployment-84b7b6b5d4-qxfbs   1/1     Running   0        10d

3. Fetch logs for your application from a pod. Replace the <pod-name> placeholder with the pod name of the previous step.

   kubectl logs --tail=100 <pod-name>

   Example:

   $ kubectl logs --tail=100 webapp01-deployment-84b7b6b5d4-5lnhb
   Not a secure app, removing idcs.jsp
   Jan 21, 2019 9:16:53 AM org.apache.coyote.AbstractProtocol init
   INFO: Initializing ProtocolHandler ["http-bio-8080"]
   Jan 21, 2019 9:16:53 AM org.apache.catalina.core.StandardService startInternal
   INFO: Starting service Tomcat
   Jan 21, 2019 9:16:53 AM org.apache.catalina.core.StandardEngine startInternal
   INFO: Starting Servlet Engine: Apache Tomcat/7.0.50
   Jan 21, 2019 9:16:53 AM org.apache.catalina.startup.ContextConfig getDefaultWebXmlFragment
   INFO: No global web.xml found
   Jan 21, 2019 9:16:53 AM org.apache.coyote.AbstractProtocol start
   INFO: Starting ProtocolHandler ["http-bio-8080"]
   Jan 21, 2019 6:56:47 PM org.apache.coyote.http11.AbstractHttp11Processor process
   INFO: Error parsing HTTP request header
    Note: further occurrences of HTTP header parsing errors will be logged at DEBUG level.