netfilter-mailcow flooding iptables

alexteixeira

my mailcow are flood iptbles with this insert:

docker-compose logs -f –tail=20 netfilter-mailcow

netfilter-mailcow_1 | Added POSTROUTING rule for source network 172.22.1.0/255.255.255.0 to SNAT target 179.x.x.x
netfilter-mailcow_1 | Added POSTROUTING rule for source network 172.22.1.0/255.255.255.0 to SNAT target 179.x.x.x
netfilter-mailcow_1 | Added POSTROUTING rule for source network 172.22.1.0/255.255.255.0 to SNAT target 179.x.x.x
netfilter-mailcow_1 | Added POSTROUTING rule for source network 172.22.1.0/255.255.255.0 to SNAT target 179.x.x.x

there are many of this, flooding my iptables, someone with this too?

Mobitux

On my server it is the same.

alexteixeira

Nobody else with the same problem?

dk1981n

I have the same problem

alexteixeira

@diekuh can you help us?

beerlao

I have the same problem. Additionally, server.py from netcow-mailfilter eats up to 100% CPU time.

solsocog

mailcowdockerized-netfilter-mailcow-1 | Added POSTROUTING rule for source network 172.22.1.0/255.255.255.0 to SNAT target 5.x.x.x
mailcowdockerized-netfilter-mailcow-1 | Error in FORWARD chain: MAILCOW target not found, restarting container
mailcowdockerized-netfilter-mailcow-1 | Error in INPUT chain: MAILCOW target not found, restarting container
mailcowdockerized-netfilter-mailcow-1 | Error in FORWARD chain: MAILCOW target not found, restarting container
mailcowdockerized-netfilter-mailcow-1 | Error in INPUT chain: MAILCOW target not found, restarting container
mailcowdockerized-netfilter-mailcow-1 | Clearing all bans
mailcowdockerized-netfilter-mailcow-1 | Unbanning 172.245.x.x
mailcowdockerized-netfilter-mailcow-1 | Clearing all bans
mailcowdockerized-netfilter-mailcow-1 | Initializing mailcow netfilter chain
mailcowdockerized-netfilter-mailcow-1 | Watching Redis channel F2B_CHANNEL
mailcowdockerized-netfilter-mailcow-1 | Added POSTROUTING rule for source network 172.22.1.0/255.255.255.0 to SNAT target 5.x.x.x

I’m having chain issues since using snat.

iptables-legacy –list
Chain INPUT (policy ACCEPT)
target prot opt source destination
MAILCOW all – anywhere anywhere

Chain FORWARD (policy ACCEPT)
target prot opt source destination
MAILCOW all – anywhere anywhere

Chain OUTPUT (policy ACCEPT)
target prot opt source destination

Chain MAILCOW (2 references)
target prot opt source destination

othiman

Hi. I have the exact same problem. Every 10 seconds a new entry is added to the POSTROUTING chain of iptables. I just updated the system to the lasted version of mailcow, but the problem persists.
The host system is a Ubuntu 20.04 with Docker version 20.10.17, build 100c701. I activated SNAT via the according entries for IPv4 and IPv6.
Has anyone found a solution for this?

othiman

A hotfix solution can be found in the issue here: mailcow/mailcow-dockerized#4658 (comment)
Hopefully mailcow/mailcow-dockerized#4724 will be merged soon to finally fix the problem.
Current issue where this error is tracked: mailcow/mailcow-dockerized#4697