On Wed 31 Mar 2021 at 18:28:52 (-0400), Dan Norton wrote: > David Christensen wrote on Wed, 31 Mar 2021 13:49:56 -0700: > > I would do 'apt-get update' and 'apt-get upgrade' ('autoremove', > 'clean', etc.). Once apt-get(8) is done, I would revert the changes > to /etc/resolv.conf and see if name resolution breaks or remains > working. (I would test by renaming /etc/resolve.conf and rebooting.) > > Here is what I did: > # apt update > # apt upgrade > # apt autoremove > # apt-get clean > # cp /etc/resolv.conf /etc/resolv.confX > # chattr -i /etc/resolv.conf > ## to make resolv.conf *not* immutable > # cat /etc/resolv.conf > domain attlocal.net > search attlocal.net
I don't recall your answering Alexander's question: what benefit are you getting from those two lines? Do you have a number of machines at home that are being placed in that domain, whose names you resolve with att's help? > nameserver 1.1.1.1 > nameserver 1.0.0.1 > nameserver 192.168.1.254 Yes, BT do this (use the highest host number rather than the lowest). > Shutdown then power-on boot > > ## rebooted with /etc/resolv.conf *not* immutable > root@deb4:~# ping google.com > ping: google.com: Temporary failure in name resolution > root@deb4:~# cat /etc/resolv.conf > domain attlocal.net > search attlocal.net > nameserver 192.168.1.254 > ## showing that /etc/resolv.conf has been clobbered Normally, I would say that you'd expect that, because dhclient would overwrite it with DHCP information returned from your router. But we've a clue that your system is very different from, say, mine: '# systemctl status systemd-resolved shows it being active and "Processing requests...".' and in a parallel thread "Moritz Kempe: DNS problems on Raspberry Pi 400 (Debian 10.9)" we saw: "hosts: files mdns4_minimal [NOTFOUND=return] dns mymachines" which smells of nss-resolve and, hence, systemd-resolved. I notice that man nss-resolve also mentions placing "resolve" early in the hosts: line. Now, I'm not saying that any of this last applies to your system, but it does suggest that, because you're using systemd-resolved, some of the advice being given by users who aren't, might not directly apply. BTW we haven't seen your own nsswitch.conf. > After restoring resolv.conf so that it looks like this: > # cat /etc/resolv.conf > domain attlocal.net > search attlocal.net > nameserver 1.1.1.1 > nameserver 1.0.0.1 > nameserver 192.168.1.254 > # chattr +i /etc/resolv.conf > ## making it immutable > > Rebooted and posted this. If you're going to file a bug, I would first start by reading up on systemd-resolved, and checking that your configuration matches what that service expects. If that doesn't fix it, then I'd file the bug against systemd-resolved, ie libnss-resolve. I'm not sure whether that was in the point-release, but the DDs can always reassign it. Cheers, David.