Missing "Additional DNS Servers"

[Lonnie Lee Best]

Ubuntu 19.04 uses the gnome-control-panel's network manager, and it is missing the feature for adding "Additional DNS Servers".

Here's that feature as it looked in Ubuntu 16.04:
https://i.imgur.com/j3nF1nu.png

Notice the "Additional DNS Servers" feature above. Here's that same tab as shown in Ubuntu 19.04 via gnome-control-panel:
https://i.imgur.com/XwRPnRS.png

When you auto-connect to a LAN, you will automatically receive a DNS server from dhcp. While that DNS server may be really good at resolving local computers, it may not be able to resolve everything. So, it is nice to both "be able to keep that dns server issued by dhcp" and also "add additional DNS servers" for resolving non-local domains that the issued dns server may not be able to resolve.

Essentially, it tells the network manager, if you can't resolve this domain from this local DNS server, try checking with these DNS servers too.

This is a regression of functionality (compared to Ubuntu 16.04). Please add it back.

ProblemType: Bug
DistroRelease: Ubuntu 19.04
Package: gnome-control-center 1:3.32.1-1ubuntu4
ProcVersionSignature: Ubuntu 5.0.0-13.14-generic 5.0.6
Uname: Linux 5.0.0-13-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.10-0ubuntu27
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Tue Apr 23 05:08:01 2019
InstallationDate: Installed on 2019-01-07 (105 days ago)
InstallationMedia: Ubuntu 16.04.5 LTS "Xenial Xerus" - Release amd64 (20180731)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: gnome-control-center
UpgradeStatus: Upgraded to disco on 2019-04-21 (2 days ago)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Lonnie Lee Best (launchpad-startport)]

Actually, I think this does work, it is just labeled differently.

As long as it allows you to have both the "automatically acquired DNS server" (from DHCP) and at the same time have "Additional DNS Servers", I think we're good here.

[Sebastien Bacher (seb128)]

Upstream closing the bug with that comment

'Well, you're right that it's just a different UI for what is called "Additional DNS Servers" in nm-connection-editor. So it doesn't matter which one you use; you should get the same result either way. Hence, I'm going to close this issue.
But no, that is not how the feature works. What happens is any one of the DNS servers will be used. The next DNS server will be tried only if the first one is broken. That is, if the first DNS server successfully returns a negative result, then the others will never be queried.
To get the behavior you're looking for, you would need to make changes to systemd-resolved to add an option for that (which might not be accepted), and then add another option in NetworkManager to enable the systemd-resolved option. Only if NetworkManager API exists could we expose UI for this in gnome-control-center.'

Doing the same for the launchpad bug