All my household devices are connected via Wi-Fi to the main router ( tp link c6 v2) while my laptop is connected via ethernet cable to the same router. I have no problems with this setup while my second router (tp link c6 v3, openwrt + wireguard) is turned off -> Most of the time I keep the openwrt router turned off, I only turn it on when I need to use the wireguard tunnel to access my home network from outside the household.
The problem is:
Whenever I turn on the second router for wireguard (everything is working flawlessly in this regard), my laptop that is connected to the first router via ethernet/Wi-Fi is losing connection from time to time ( about every 10 mins). It fixes itself if I unplug the ethernet cable for 5 seconds and replug it/ reconnecting to the wi-fi. This doesn't happen with my other household devices like phones or chromecast.
Let's see the final config of your OpenWrt router...
Please copy the output of the following commands and post it here using the "Preformatted text </> " button:
Remember to redact passwords, MAC addresses and any public IP addresses you may have:
Ok, I removed these. I will test for a couple of days and tell you the result. I assumed that these settings needed to be there because I have a dynamic ip. The connection from my phone seems to work even with them removed from openwrt (the config file on my phone was not changed).
Yo, if the wireguard server receives a handshake from the client, and then the client reboots, if theres no rtc clock battery, it will have a different system time.
Wire guard is expecting the new handshake timestamp to be after the last sucessful handshake, if openwrt boots and uses the last modified file as its time, then its clock will be minutes, hours, days behind.
When a wireguard interface is restarted, theres no last handshake to compare against, so it accepts any timestamp.
Theres a wireguard watchdog script which will reset any peeers after a specified timeout, so theyre always ready to accept new handshake if disconnected for nore than, say 5 minutes
This could be why reconnecting the ethernet helps, because that also resets the wireguard peers.
While your statement about the requirement for accurate time is correct, it would not explain the OPs described issue where a computer (not connected to Wireguard) loses connectivity when the WG router is plugged into the main network.
Another question based on my setup is : if I enable the hardware offloading setting to try and get better speeds over wireguard - will this have an effect on my current setup? (should I leave them off - software/hardware or try to enable them?)
No, HW offloading will not affect your upstream network.
I don't know if it will help, hurt, or be neutral in terms of WG performance. You can try it -- it shouldn't cause any problems (other than potentially slower speeds if it does indeed degrade performance).
It seems that I'm still losing access to the internet from time to time ( about every 1-2 hours). I noticed that when doing heavy connection tasks like playing games via streaming on geforce now. The same fix works - removing the ethernet cable from my laptop and plugging it back in.
I cannot see any network based reason why the laptop would be affected by the presence of the WG router.
There is one possible scenario, though -- you could have a marginal power supply on the first router (the C6 v2) which could cause brownouts in the device which would have the potential to hang the ethernet port. This would be triggered by events that require more electrical power such as high-bandwidth downloads, but may only be tipped over the edge when there is an additional ethernet port in use with a reasonable amount of traffic flowing through it.
So... check your power adapter -- are you using a 12V DC @ 1.0A power adapter on that device (that's the spec from the website). Do you have another one available (12V @ 1A or greater)? You could try swapping the power supplies between the two Archer C6 devices.
Both power adapters are rated 12V @ 1A, I will try to swap them, maybe the one on the main router is faulty.
I thought the problem could be from the fact that on my WG clients setup I use the DNS address of my isp, the one that also the main router ( C6 v2) is using, instead of using a public one like Cloudflare (1.1.1.1). But this might have nothing to do with it?
The WG router is acting in the capacity of a lan client to your main router. The routed clients (i.e. WG peers) are masqueraded as a function of the lan firewall zone on the WG router. This means that the main router isn't aware of anything happening on the WG router except for general traffic that is in transit... in other words, all traffic simply goes to, or comes from 192.168.0.2 -- it doesn't know anything more about the nature of that traffic or that there are WG peers that are routed through it.
