Change what DNS server is used for nameserver lookups in Ubuntu 18

Tue, Oct 22, 2019

I think my main problem is CenturyLink is terrible, and i don’t want to use its DNS. But i also don’t want to use DNS from whichever network i happen to be connected to, so i want an on-my-laptop setting (not my router) that is used regardless of whether i’m plugged in to ethernet or connected to absolutely any wireless network.

how to see what is handling dns on my computer
good goddamn holy hell why is it impossible to set alternate nameservers like opendns for Ubuntu, regardless of which wifi connection is used, these days?
192.168.1.1

cat /etc/network/interfaces
# ifupdown has been replaced by netplan(5) on this system.  See
# /etc/netplan for current configuration.
# To re-enable ifupdown on this system, you can run:
#    sudo apt install ifupdown

ls -la /etc/netplan/
total 16
drwxr-xr-x   2 root root  4096 Apr 23  2018 .
drwxr-xr-x 182 root root 12288 Oct 22 11:50 ..

Nada. Nothing there. What the heck is controlling my network DNS on this computer?

cat /run/systemd/resolve/resolv.conf
# This file is managed by man:systemd-resolved(8). Do not edit.
#
# This is a dynamic resolv.conf file for connecting local clients directly to
# all known uplink DNS servers. This file lists all configured search domains.
#
# Third party programs must not access this file directly, but only through the
# symlink at /etc/resolv.conf. To manage man:resolv.conf(5) in a different way,
# replace this symlink by a static file or a different symlink.
#
# See man:systemd-resolved.service(8) for details about the supported modes of
# operation for /etc/resolv.conf.

nameserver 192.168.1.1

sudo vim /etc/resolvconf/resolv.conf.d/base

And put this in there:

ameserver 1.1.1.1
nameserver 1.0.0.1
nameserver 2606:4700:4700::1111
nameserver 2606:4700:4700::1001

sudo resolvconf -u
sudo service network-manager restart

But still exactly the same server beeing used for lookup, arghhh:

nslookup agaric.coop
Server:		127.0.0.53
Address:	127.0.0.53#53

Non-authoritative answer:
Name:	agaric.coop
Address: 162.247.75.218

Not much clue in the log?

Oct 22 18:57:17 oryx systemd-resolved[1177]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.
Oct 22 18:57:17 oryx nm-dispatcher: req:6 'connectivity-change': start running ordered scripts...
Oct 22 18:57:19 oryx goa-daemon[4271]: /org/gnome/OnlineAccounts/Accounts/account_1529698497_0: Setting AttentionNeeded to FALSE because EnsureCredentials() succeded
Oct 22 18:57:24 oryx systemd-resolved[1177]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.
Oct 22 18:57:24 oryx systemd-resolved[1177]: message repeated 4 times: [ Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.]
Oct 22 18:57:27 oryx systemd[1]: NetworkManager-dispatcher.service: Succeeded.
Oct 22 18:57:38 oryx systemd[1]: systemd-hostnamed.service: Succeeded.

After trying every damn thing short of the wifi-connection-specific configuration, it still is using the wrong DNS servers:

systemd-resolve --status wlp3s0
Link 3 (wlp3s0)
      Current Scopes: DNS
DefaultRoute setting: yes
       LLMNR setting: yes
MulticastDNS setting: no
  DNSOverTLS setting: no
      DNSSEC setting: no
    DNSSEC supported: no
  Current DNS Server: 192.168.1.1
         DNS Servers: 192.168.1.1
          DNS Domain: ~.

So i finally gave in and did the wifi-specific configuration, and it at least mostly sees the wanted DNS server:

systemd-resolve --status wlp3s0
Link 3 (wlp3s0)
      Current Scopes: DNS
DefaultRoute setting: yes
       LLMNR setting: yes
MulticastDNS setting: no
  DNSOverTLS setting: no
      DNSSEC setting: no
    DNSSEC supported: no
  Current DNS Server: 1.1.1.1
         DNS Servers: 192.168.1.1
                      1.1.1.1
                      1.0.0.1
          DNS Domain: ~.

BUT IT’S STILL NOT USED (not that the earlier one was actually used either?)

nslookup agaric.coop
Server:		127.0.0.53
Address:	127.0.0.53#53

Non-authoritative answer:
Name:	agaric.coop
Address: 162.247.75.218

That first server should be 1.1.1.1, aaauugggghhhhh!

ls -l /etc/resolv.conf
lrwxrwxrwx 1 root root 29 Jun 22  2018 /etc/resolv.conf -> ../run/resolvconf/resolv.conf

cat /run/systemd/resolve/resolv.conf
# This file is managed by man:systemd-resolved(8). Do not edit.
#
# This is a dynamic resolv.conf file for connecting local clients directly to
# all known uplink DNS servers. This file lists all configured search domains.
#
# Third party programs must not access this file directly, but only through the
# symlink at /etc/resolv.conf. To manage man:resolv.conf(5) in a different way,
# replace this symlink by a static file or a different symlink.
#
# See man:systemd-resolved.service(8) for details about the supported modes of
# operation for /etc/resolv.conf.

nameserver 192.168.1.1
nameserver 1.1.1.1
nameserver 1.0.0.1

sudo ln -sf /run/systemd/resolve/resolv.conf /etc/resolv.conf

… and now it’s using 192.168.1.1 which, whatever it is, is less broken than 127.0.0.53? And i can actually connect to agaric.zulipchat.com which was blocked. Still don’t understand anything, sob

But good enough for now.

nslookup agaric.coop
Server:		192.168.1.1
Address:	192.168.1.1#53

Non-authoritative answer:
Name:	agaric.coop
Address: 162.247.75.218

hahahahaha that is probably the stupidest thing i had to do on linux and i still don’t have it how i want or have any clue what’s going on, but i’m now using slightly less-stupid DNS?

Resources tried: