Configuring Linux DNS
There are an incredible number of ways to configure DNS on Linux.
Tailscale attempts to interoperate with any Linux DNS configuration it finds already present. Unfortunately, some are not entirely amenable to cooperatively managing the host’s DNS configuration.
If you’re using both NetworkManager and systemd-resolved (as in
common in many distros), you’ll want to make sure that
/etc/resolv.conf is a symlink to
/run/systemd/resolve/stub-resolv.conf. That should be the
default. If not,
$ sudo ln -sf /run/systemd/resolve/stub-resolv.conf /etc/resolv.conf
When NetworkManager sees that symlink is present, its default behavior is to use systemd-resolved and not take over the resolv.conf file.
After fixing, restart everything:
$ sudo systemctl restart systemd-resolved
$ sudo systemctl restart NetworkManager
$ sudo systemctl restart tailscaled
Without any DNS management system installed, DHCP clients like
dhclient and programs like
tailscaled have no other options than
/etc/resolv.conf file themselves, which results in
them sometimes fighting with each other. (For instance, a DHCP renewal
resolv.conf resulting in loss of MagicDNS functionality.)
Possible workarounds are to use
Issue 2334 tracks making Tailscale react to other
resolv.conf so Tailscale can add itself back.