[dev] debug packets - output

Hi all, I am trying to debug eigrp process in FRR and I can't figure out, how to get any output from 'debug eigrp packets all'. Nothing shows up anywhere. Initially, I thought, that I will see the output directly in vtysh as the packets come, but I don't see anything. I tried to set logging to an output file - it gets created but no output in the file. I don't see anything in /var/log/frr either. Can anyone give me a hint as to where and how to get the debugging running? Or any other logging to that matter? Thanks and regards. Michal Ruprich