Re: Amavisd listening on multiple UDP ports
Danilo Godec <[email protected]> Thu, 19 Sep 2024 08:07:51 +0200
| Newsgroups | gmane.mail.virus.amavis.user |
|---|---|
| Organization | Agenda d.o.o. |
| Message-ID | <[email protected]> |
On 19. 09. 24 03:01, Roger Marquis wrote: > Is there any way to disable these (random?) UDP listening ports > (47998|32542|14380|34448|45248|22313|26237|61057) or any downside > to filtering them? > > Roger > > # lsof | grep -w vscan | grep UDP > 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->*:* > perl 79715 vscan 10u IPv4 0xfffff8010be3c340 0 UDP > $amavis.ip:43712->$nameserver.ip:53 > perl 79715 vscan 11u IPv4 0xfffff80151d19dc0 0 UDP *:32542->*:* > perl 79716 vscan 10u IPv4 0xfffff8005a7cb300 0 UDP > $amavis.ip:49013->$nameserver.ip:53 > perl 79716 vscan 12u IPv4 0xfffff800215cfac0 0 UDP *:14380->*:* > perl 79717 vscan 10u IPv4 0xfffff8005a7cb140 0 UDP *:34448->*:* > perl 79717 vscan 11u IPv4 0xfffff80336cb4f20 0 UDP > $amavis.ip:21362->$nameserver.ip:53 > perl 79718 vscan 10u IPv4 0xfffff8008a018c60 0 UDP *:45248->*:* > perl 79718 vscan 11u IPv4 0xfffff800702ece40 0 UDP > $amavis.ip:43194->$nameserver.ip:53 > perl 79719 vscan 10u IPv4 0xfffff8010be3cdc0 0 UDP *:22313->*:* > perl 79719 vscan 11u IPv4 0xfffff800da7546a0 0 UDP > $amavis.ip:12460->$nameserver.ip:53 > perl 79720 vscan 10u IPv4 0xfffff800702ec220 0 UDP *:26237->*:* > perl 79720 vscan 11u IPv4 0xfffff800661973c0 0 UDP > $amavis.ip:21489->$nameserver.ip:53 > perl 79721 vscan 10u IPv4 0xfffff802d3897920 0 UDP *:61057->*:* > perl 79721 vscan 11u IPv4 0xfffff80066197800 0 UDP > $amavis.ip:43299->$nameserver.ip:53 > These look like DNS lookups going from *$amavis.ip:[random_port]* to *$nameserver.ip:53*. I guess filtering them could have some downsides. D.