Packet loss on server running Docker

Hi,

Last few days I’ve been experiencing about 20% packet loss when Docker is running. Whenever I stop Docker the server no longer has connectivity issues.

I think it’s something with IPTables. See output below:

plex@plex:~$ sudo iptables --list
Chain INPUT (policy ACCEPT)
target prot opt source destination

Chain FORWARD (policy DROP)
target prot opt source destination
DOCKER-USER all – anywhere anywhere
DOCKER-ISOLATION-STAGE-1 all – anywhere anywhere
ACCEPT all – anywhere anywhere ctstate RELATED,ESTABLISHED
DOCKER all – anywhere anywhere
ACCEPT all – anywhere anywhere
ACCEPT all – anywhere anywhere

Chain OUTPUT (policy ACCEPT)
target prot opt source destination

Chain DOCKER (1 references)
target prot opt source destination
ACCEPT tcp – anywhere 172.17.0.2 tcp dpt:9000
ACCEPT tcp – anywhere 172.17.0.3 tcp dpt:9091

Chain DOCKER-ISOLATION-STAGE-1 (1 references)
target prot opt source destination
DOCKER-ISOLATION-STAGE-2 all – anywhere anywhere
RETURN all – anywhere anywhere

Chain DOCKER-ISOLATION-STAGE-2 (1 references)
target prot opt source destination
DROP all – anywhere anywhere
RETURN all – anywhere anywhere

Chain DOCKER-USER (1 references)
target prot opt source destination
RETURN all – anywhere anywhere

OS: Ubuntu 18.04
Containers: Portainer, PLEX and transmission-openvpn

If anybody has a clue what could be wrong, let me know :slight_smile: