The maas/stable/ubuntu xenial repository does not have a Release file

Question

When I run sudo apt update on my Ubunutu 16.04 LTS Server with MAAS installed I get the following error message:

graeme@MAAS:~$ sudo apt update
Hit:1 http://gb.archive.ubuntu.com/ubuntu xenial InRelease
Hit:2 http://security.ubuntu.com/ubuntu xenial-security InRelease
Ign:3 http://ppa.launchpad.net/maas/stable/ubuntu xenial InRelease
Hit:4 http://gb.archive.ubuntu.com/ubuntu xenial-updates InRelease
Err:5 http://ppa.launchpad.net/maas/stable/ubuntu xenial Release
  404  Not Found
Hit:6 http://gb.archive.ubuntu.com/ubuntu xenial-backports InRelease
Reading package lists... Done
E: The repository 'http://ppa.launchpad.net/maas/stable/ubuntu xenial Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.

Is this something I should ignore or try and fix?

Answer 1

Turns out there isn't a stable release of MAAS for Xenial which means I need to be on the ppa:maas/next repository instead of ppa:maas/stable. The issue was brought about after stepping through the MAAS getting started guide which wanted asked me to ad the ppa:maas/stable repository. After removing it with

sudo add-apt-repository --remove ppa:maas/stable

The update went without any errors.