COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME perl 79714 vscan 10u IPv4 0xfffff80164e96b40 0 UDP $amavis.ip:59511->$nameserver.ip:53 perl 79714 vscan 12u IPv4 0xfffff802071cb880 0 UDP *:47998->*:*
Very interesting. In my tests, the second line (listening socket) is the result of Amavis' DKIM verifier, while the first line is spawned by SpamAssassin. The listening socket is used only until SpamAssassin has been loaded by the first mail which does not bypass spam checks, because SpamAssassin overrides the `persistent_udp` option initially set to `1` by Amavis.
Is there any way to disable these (random?) UDP listening ports
There is no Amavis confvar for the `persistent_udp` option. You would have to modify the executable.
