Christoph Anton Mitterer wrote, regarding rpcbind, some four years ago: > It seems to always reserve one random (not 873) port in addition... why > does it do so at all?
I think it's used to make remote "callit" requests, to receive their asynchronous replies and to forward those replies onto the original requester. Portmap used to fork() to do this synchronously. More at: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=870579: rpcbind callit replies from a random reserved udp port, making firewalling hard Sorry for dredging up this old news but perhaps someone's still interested.
