ok - I took a bit different approach. Since I know what error in rabbitmq's log file is associated with things coming to a stop on fedia.io, I installed swatchdog and set it up to look for that word (which is, btw, "timeout"). I created a script that stops all the messengers, then stops php-fpm, keydb, and rabbitmq. Then it start rabbit, keydb, and php-fpm in order. Finally, it restarts the messengers.
I will be surprised if it works first time, so it may still crash again but I'll be watching
testing
Fitik