Strange speed issue interaction between router and docker container [Unraid & VLAN]

[stuntard]

OK so this is going to be a bit of a strange one.

I have sabNZBd running in a Docker container on Unraid. No problems there, works great, maxes out my connection etc.
My router is a Mikrotik RB5009 and my network is split up with VLANs, again everything works great.

My problem is this....when I add a virtual ethernet interface to my bridge in my router, my speed in sabNZBd tanks hard.. and no one on the Mikrotik forums can tell me why. The funny thing is, is I can run the client on my Windows desktop..speed is fine.. I can run a speedtest on the same Unraid server, and the speed is fine. I can download using jDownloader or another client from inside a Docker container, and the speed is fine. But they second I add a VETH interface on my bridge on the router, speeds goes way down. The second I remove it, it goes back up again.

The reason I am using the VETH interface on the router is that it is required to run containers on the router itself (I want to run Adguard on the router).
There has to be some strange interaction between the docker container and the router somehow. The VETH interface isn't even on the same network subnet as my Unraid server, it just has to exist for the problem to appear.

[sander]

#UnraidAlert !

SABnzbd knows nothing about VLANs. So something in docker in general, or Unraid, or you router?

> There has to be some strange interaction between the docker container and the router somehow.

You can try another docker container, with iperf3, with and without VLAN:

Code: Select all

$  docker run  -it --rm networkstatic/iperf3 -c ams.speedtest.clouvider.net 
Connecting to host ams.speedtest.clouvider.net, port 5201
[  5] local 172.17.0.3 port 37892 connected to 194.127.172.176 port 5201
[ ID] Interval           Transfer     Bitrate         Retr  Cwnd
[  5]   0.00-1.00   sec   193 MBytes  1.62 Gbits/sec    2   1.29 MBytes       
[  5]   1.00-2.00   sec   218 MBytes  1.82 Gbits/sec    0   1.41 MBytes       
[  5]   2.00-3.00   sec   239 MBytes  2.00 Gbits/sec    0   1.53 MBytes       
[  5]   3.00-4.00   sec   258 MBytes  2.16 Gbits/sec    0   1.65 MBytes       
[  5]   4.00-5.00   sec   271 MBytes  2.27 Gbits/sec    0   1.76 MBytes       
[  5]   5.00-6.00   sec   278 MBytes  2.33 Gbits/sec    0   1.88 MBytes       
[  5]   6.00-7.00   sec   281 MBytes  2.36 Gbits/sec    0   1.98 MBytes       
[  5]   7.00-8.00   sec   280 MBytes  2.35 Gbits/sec    0   2.08 MBytes       
[  5]   8.00-9.00   sec   280 MBytes  2.35 Gbits/sec    0   2.18 MBytes       
[  5]   9.00-10.00  sec   280 MBytes  2.35 Gbits/sec    0   2.27 MBytes       
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate         Retr
[  5]   0.00-10.00  sec  2.52 GBytes  2.16 Gbits/sec    2             sender
[  5]   0.00-10.02  sec  2.52 GBytes  2.16 Gbits/sec                  receiver

iperf Done.

[stuntard]

That is why I am confused as to why it happens. VLANs should not come into in regardless. There is no intervlan communication going on so for all intents and purposes it is just a single network. I only mentioned them in the off chance someone else had the same setup. The virtual ethernet interface on the router that causes the problem isn't even part of a vlan, nor does it have any traffic. Just existing is enough to freak sab out. Unraid isn't even using VLANs it's just connected to the router via an untagged port. I've used a speed test docker container, as well as 2 other download clients to test and they don't slow down.

I'm clutching at straws here as I can't see any reason why it should be happening. I've posted in the Unraid forums as well to see if they may have answers. The Mikrotik guys say it shouldn't happen, and in 99% of cases it doesn't.

[sander]

If you think it's your router, you can even do the iperf3 speedtest without docker.

And if you think it's your router, try without that router.

HTH