Hello Marc Lehmann, in that situation an strace is probably not that helpful. Maybe you can provide a backtrace while the program is frozen.
You might use following in a different terminal: (Basically attaches a debugger every 30 seconds, prints the backtrace and detaches.) while true; do echo ---- $(date); cat /proc/$(pidof roger)/stack; gdb -q -ex bt -ex detach -ex quit --pid $(pidof roger); sleep 30s; done Even better if debug symbols would be installed like described in [1]. At least roger-router-dbgsym, better for the shown shared objects in the backtrace too (if available in stretch). Kind regards, Bernhard [1] https://wiki.debian.org/HowToGetABacktrace
