Network stopped working - invalid DNS settings

Software PureOS
1

I’ve spent the last two months using my Librem 13v1 quite successfully while on a vacation. I was using the local wifi connection, and had no trouble with network.

Now I got home, and I couldn’t get any network connectivity. The laptop did connect to my home wifi, but couldn’t find any websites. The same happened when I plugged in the network cable and disabled wifi.

Looking into it, I found out that my /etc/resolv.conf said “nameserver 192.168.1.1”

As far as I know, there’s nothing in that IP address on my home network. I’ve tried manually setting the DNS servers to 8.8.8.8 under Settings/Wifi|Network/[settings]/IPv4, but that seemed to do nothing.

In the end I edited the my resolv.conf manually (“nameserver 8.8.8.8”), and got things working. I have a few questions:

  • What happened? It looks to me like my laptop automatically configured for the vacation wifi, and then got stuck with those settings for some reason.

  • Why didn’t editing the network settings via the GUI settings app work?

  • Is something going to overwrite my resolv.conf, like the warning in that file indicates?

Thanks for any help.

2

Hi @Erno_Kaikkonen,

The IP 192.168.1.1 seems to be the DNS server provided by your network.
Do you know if your laptop uses a static ip, or uses DHCP to get an IP ?

If the IP is configured with DHCP, it will ask the DHCP server for the IP of the DNS server.
If not, your /etc/resolv.conf will be left untouched.

Debian wiki’s NetworkManager page might help as well. PureOS is based on Debian, and should behave mostly in the same way.

3

to elaborate a little on previous post… if you wish to keep using dhcp for dynamically allocated ip address, but dont want the dns to be updated from whatever the settings are in the router you are using you can configure your dns in /etc/dhcp/dhclient.conf
if you want to use the google nameserver for example

supersede domain-name-servers 8.8.8.8, 8.8.4.4;

4

Thank you for your answers. While they do shed some light on the technical side of my issue, I’m still left wondering what actually happened.

My point is that I simply used some wifi networks, and as a result, my network configuration got borked. I never touched any configurations. I simply connected to wifi, entered the credentials and did my emails and web and such. And then I ended up in a situation where I needed to go edit configuration files by hand. The way I see it, this just shouldn’t happen.

If I had a way of reproducing the problem, I’d add the steps here, but unfortunately the other network is on the other side of the world, so that’s not going to happen. I guess I’ll just add the incident to the list of “stuff that happens with desktop Linux” and move on.