Unknown network problem

Today I connected my 20.09 machine in another network and had no connectivity. It is again a wired connection. On the same wire other devices work fine - android TV for example. The machine successfully recevies a DHCP address in the same network where the gateway is. The gateway pings OK. However, names are not resolved. I set-up and now sometimes they are resolved, sometimes not. Sometimes nslookup returns Query refused. Then I tried to ping and it didn’t work - I got no response.
Now I am completely not sure what’s going on - if it is not a DNS problem what is it?

Maybe it’s related to this issue https://github.com/NixOS/nixpkgs/issues/107537 ? There seems to be an upstream problem with systemd-resolved. However, you’re on 20.09, so I would expect you not to be affected. If you are, then the problem is a bit more serious than first anticipated.

@Samae thank you very much. I upgraded and the problem is gone. It was very weird and it is great I won’t have to dig into it any longer.

I just found out the root cause. It wasn’t related to the issue in question. A virtual machine had the same IP as my current network gateway.

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