So when I start up a Linux Shell runner without a working internet connection, it just throws a lot of Java exceptions. Took me a while to figure out that my internet connection was not working, because there wasn't any notification it was "OFFLINE", just a lot of Java exceptions.
Not really a question, this just seems to be a bug in the Bitbucket Pipelines selfhosted runner.
Log (note: when it reports as "OFFLINE" I manually cancelled the runner because it wasn't working properly):
https://pastebin.com/RvJDSAyW
Update: Similar thing happens when you try to start it with the runner disable in Bitbucket settings:
https://pastebin.com/iCwYNnU9