My apologies, Gabor, but we don’t have a working example for Axon Framework with JGroups other than the test cases inside the JGroups Extension.
I do think there is a benefit in the extension containing a sample.
As (working) life goes, we at AxonIQ are pretty busy, sadly enough.
I can tell you, though, that when I used the JGroups solution in the best, starting with the configuration as used by the tests cases helped me for a minimal use case.
From there on out, I always specified the configuration further for the application I was working on.
I know this isn’t exactly what you were looking for, Gabor, but I do hope it helps you (a little) further.