Tracked connections grows forever?

I have recently noticed that the number of tracked connections on my Turris Omnia seems to continue to grow and never shrink untill reset. I’m not sure what is causing it.

I’m prettu sure there are no devices using this many connections. and the number of tracked connections resets to zero if i reset the router.

Did you compare to output of conntrack -C?

root@degganet:~# conntrack -C

Since you suspect this being an unrealistic high count for your network use case there could be two causes (I could think of)

  • kernel bug
  • some node on your network actually generating that amount of egress traffic

and you might want to investigate - I would:

  • try to isolate O’s client nodes (that incl. any LXC container that might be deployed on the O) one by one (either physically disconnect or on the O block through firewall) in order to find the node that potentially generates the amount of connections, and/or
  • monitor on the O with conntrack -E, and/or
  • monitor packet flow on the O with wireshark’s ssh remote feature

If that yields a client node with an unusual high count of connections inspect such node for the potential cause. If it does not yield a client node as potential culprit see if the O itself is somehow causing it, e.g. shutdown inessential daemons/services.