TL;DR

Recently, during the normal software upgrade process (i.e., apt upgrade or apt dist-upgrade) I started getting messages like this:

[...]

The following packages have been kept back:

  [...]

0 upgraded, 0 newly installed, 0 to remove and [...] not upgraded.

What are my options?

^{Note: This is not a duplicate of the myriad similar questions asked already here. You should consider my question as a follow-up to this question.}

I had exactly the same problem on my main Ubuntu 22.04 system as the question mentioned above. I changed servers, tried to manually install the named package, and somehow the problem was solved, yesterday. Today, when I tried to install any new updates, I got the message that I had 32 packages that have been kept back.

I have a similar 22.04 version (virtual) Ubuntu installation, which is fully updated now and this problem does not yet occur there (with a similar /etc/apt/sources.list file). So, I tried to compare the packages. I took the package gir1.2-gstreamer-1.0 which was "kept back" in my main system as an example and ran on my main system:

$ sudo apt --installed list | grep gir1.2-gstreamer-1.0

[...]

gir1.2-gstreamer-1.0/jammy,now 1.20.1-1 amd64 [installed,upgradable to: 1.20.3-0ubuntu1]

The same command gives the output:

gir1.2-gstreamer-1.0/jammy,now 1.20.1-1 amd64 [installed,automatic]

on my secondary (virtual) system.

Why do we have this difference? And, how can I make my main system behave as the (virtual) system where the package is installed "automatic"ally?

The output of the command apt-cache policy gir1.2-gstreamer-1.0 on my "main" system is like this:

gir1.2-gstreamer-1.0:

  Installed: 1.20.1-1

  Candidate: 1.20.3-0ubuntu1

  Version table:

     1.20.3-0ubuntu1 500 (phased 30%)

        500 http://archive.ubuntu.com/ubuntu jammy-updates/main amd64 Packages

 *** 1.20.1-1 500

        500 http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages

        100 /var/lib/dpkg/status

And on my "secondary" (virtual) system is like this:

gir1.2-gstreamer-1.0:

  Installed: 1.20.1-1

  Candidate: 1.20.1-1

  Version table:

     1.20.3-0ubuntu1 1 (phased 30%)

        500 http://archive.ubuntu.com/ubuntu jammy-updates/main amd64 Packages

 *** 1.20.1-1 500

        500 http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages

        100 /var/lib/dpkg/status

What does the value 500 (in the (phased... line) mean?

On both systems grep -ri phased /etc/apt returns nothing.

After the command sudo apt update && sudo apt upgrade gir1.2-gstreamer-1.0 was executed on my main system:

$ sudo apt --installed list | grep gir1.2-gstreamer-1.0

[...]

gir1.2-gstreamer-1.0/jammy-updates,now 1.20.3-0ubuntu1 amd64 [installed]



$ apt-cache policy gir1.2-gstreamer-1.0

gir1.2-gstreamer-1.0:

  Installed: 1.20.3-0ubuntu1

  Candidate: 1.20.3-0ubuntu1

  Version table:

 *** 1.20.3-0ubuntu1 500 (phased 40%)

        500 http://archive.ubuntu.com/ubuntu jammy-updates/main amd64 Packages

        100 /var/lib/dpkg/status

     1.20.1-1 500

        500 http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages

Now, on my secondary system I started getting this too:

$ sudo apt upgrade

Reading package lists... Done

Building dependency tree... Done

Reading state information... Done

Calculating upgrade... Done

The following packages have been kept back:

  language-pack-gnome-en

0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.