I'm running OpenWrt 18.06.1 on a TP-Link Archer C7v2. Network config is default, except that I switched of all wireless interfaces.
On my network I have a couple of servers running Debian. These servers show lots of dropped packets if I don't load the 802.1q (vlan) module. When I load the module, the rate of dropped packets disappears.
All ports on the switch on the C7 are untagged. Still it seems there are vlan tagged packets on the network.
Am I missing something? Or does anyone have an explanation why the rate of dropped packets gets to zero when I load the 802.1q module on my servers?
Sounds like debian interface is configured for vlan support but connected to an access switch port. This is unnecessary because vlan is handled by the switch.
Unless Debian is configured like this 'out of the box' I don't think so. No vlan packages have been installed. I actually had to load the 8021q module to get rid of all the dropped ethernet packets.
Thanks for all your help and suggestions so far.
The initial tcpdump I did also showed zero vlan packets. I will do some more testing when Iām back home. @gjaltemba could you please post the part of the default /etc/config/network where the VLANs on the switch are defined?
I din't do a perform a Reset in Restore, but I only changed the switch part in the network config and restarted the network service. In hindsight that wasn't a smart move, Basically I just added the "t" to the 0 and 6 ports.
Due to the fact that I use a non-default ip range, a reset wasn't an option when remote. Besides I have some custom things installed which I'd rather not loose.
Hopefuly I'll be able to access the router from the LAN connection so that I can restore the network config. If not, it's gonna be a long night (and I assume I'll have to go the failsafe route).
I do wonder why I lost my WAN connection (and hopefully the WAN connection only) by this change though.
If you tag the packets coming out of the switch to the CPU side, then you have to connect the wan and lan to tagged interfaces instead of plain eth0 and eth1. So you have similarly broken both the WAN and the LAN and will need to log in in recovery mode.
Setting it up that way initially is useful because it is simpler to add more VLANs.
When configuring the switch it is good to at least temporarily put a wifi AP on LAN so you have a way to log in if the Ethernet configuration is broken.
Recovery with failsafe went very smooth. I was up and running again in very little time. Now I still need to make the changes to the switch. Will do that soon.
Sorry for the delay. Well, I got my router up and running and removed/unloaded the 802.1q module on my linux machines. Since then I still see dropped packets. And in higher numbers then before. So I'm not sure if the issue has been fixed.