DNS problem with mullvad VPN on 18.10

Question

My mullvad VPN was working, then I upgraded to 18.10. Now when I use their UI client, it connects fine, but DNS is not working. I can ping google.com by IP but not by google.com.

I can resolve it by specifying the interface:

>resolvectl query google.com
google.com: resolve call failed: All attempts to contact name servers or networks failed

>resolvectl -i tun0 query google.com
google.com: 216.58.212.174

-- Information acquired via protocol DNS in 1.1ms.
-- Data is authenticated: no

The man page for resolvectl says this about the -i option:

Note that this option has no effect if system-wide DNS configuration (as configured in /etc/resolv.conf or /etc/systemd/resolve.conf) in place of per-link configuration is used

So is my system using per-link configuration? How do I check that?

Other info:

>ls -ld /etc/resolv.conf
lrwxrwxrwx 1 root root 29 Oct 28 10:10 /etc/resolv.conf -> ../run/resolvconf/resolv.conf

>cat /run/resolvconf/resolv.conf 
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
#     DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
# 127.0.0.53 is the systemd-resolved stub resolver.
# run "systemd-resolve --status" to see details about the actual nameservers.

nameserver 127.0.0.53

Further info as requested:

It is using openvpn 2.4.6-1ubuntu2

Output from systemd-resolve --status (when the vpn is connected):

Global
       LLMNR setting: no
MulticastDNS setting: no
  DNSOverTLS setting: no
      DNSSEC setting: no
    DNSSEC supported: no
          DNSSEC NTA: 10.in-addr.arpa
                      16.172.in-addr.arpa
                      168.192.in-addr.arpa
                      17.172.in-addr.arpa
                      18.172.in-addr.arpa
                      19.172.in-addr.arpa
                      20.172.in-addr.arpa
                      21.172.in-addr.arpa
                      22.172.in-addr.arpa
                      23.172.in-addr.arpa
                      24.172.in-addr.arpa
                      25.172.in-addr.arpa
                      26.172.in-addr.arpa
                      27.172.in-addr.arpa
                      28.172.in-addr.arpa
                      29.172.in-addr.arpa
                      30.172.in-addr.arpa
                      31.172.in-addr.arpa
                      corp
                      d.f.ip6.arpa
                      home
                      internal
                      intranet
                      lan
                      local
                      private
                      test

Link 6 (tun0)
      Current Scopes: DNS
       LLMNR setting: yes
MulticastDNS setting: no
  DNSOverTLS setting: no
      DNSSEC setting: no
    DNSSEC supported: no
  Current DNS Server: 10.9.0.1
         DNS Servers: 10.9.0.1

Link 3 (wlp1s0)
      Current Scopes: DNS
       LLMNR setting: yes
MulticastDNS setting: no
  DNSOverTLS setting: no
      DNSSEC setting: no
    DNSSEC supported: no
  Current DNS Server: 192.168.0.1
         DNS Servers: 192.168.0.1
          DNS Domain: ~.

Link 2 (eno1)
      Current Scopes: DNS
       LLMNR setting: yes
MulticastDNS setting: no
  DNSOverTLS setting: no
      DNSSEC setting: no
    DNSSEC supported: no
  Current DNS Server: 192.168.0.1
         DNS Servers: 192.168.0.1
          DNS Domain: ~.


ps auxc | grep dns returns nothing
>ps auxc | grep resolv returns:
systemd+   557  0.0  0.1  55480  9236 ?        Ss   Oct28   0:06 systemd-resolve

Answer 1

I emailed mullvad support and they suggested that I just use openvpn, i.e. same response as Coffee_Mug in: Mullvad vpn won't connect on ubuntu 18.04

On one computer, I used the old mulvad client via "env MULLVAD_USE_GTK3=yes mullvad", but on the other I got the same error as amicose in Mullvad VPN Client won't start on 18.04

For that second computer, I gave up trying to figure out why it wouldn't work and just set up openvpn to connect to one server.

Answer 2

Version 2018.6 of the Mullvad app works fine