My goal is to develop an application that will run on WebSphere Liberty hosted in Docker and eventually running on Bluemix. During development, I have installed Docker on my local Linux PC and then downloaded from IBM the base docker image containing a configured Liberty. This image is called:
registry.ng.bluemix.net/ibmliberty
I now start this image in Docker locally in my PC and attach a shell so that I can see what is going on. I find that there is a Liberty server located at
/opt/ibm/wlp/usr/servers/defaultServer
Now here comes the puzzle.
In Liberty servers I am used to working upon, the messages produced by a server are written into a "logs/messages.log" file relative to the server. This would mean that I would have expected to find the Liberty message files here:
/opt/ibm/wlp/usr/servers/defaultServer/logs/messages.log
However, when I start my server, there is nothing there.
How can I access the logs of my Liberty server obtained from the Bluemix base image (registry.ng.bluemix.net/ibmliberty) running under Docker natively on my Linux environment on my local PC?
If we examine this IBM Liberty/Bluemix documentation page:
https://console.bluemix.net/docs/images/docker_image_ibmliberty/ibmliberty_starter.html
We will find a section that reads:
Note: All ibmliberty images are configured to write Liberty log files to the directory /logs inside the container. All other files that are written by the Liberty server, are created in the directory /opt/ibm/wlp/output/defaultServer. You can access these files by using the shortcut /output.
And this is the key. The Liberty server log files can be found in /logs (that is the directory called logs south of the root of the file system).