Question is: WHY NOT? Why is it not installing it?
These are dependencies, and yet it refuses to install them.

I just run into the end of the world for my system, removing libdrm2 suddenly started to remove the whole system, which of course you can't stop.
Now it removed a million packages and I need to get my system back, because if I reboot, there will be no coming back anymore.

When I try to install kde-standard, I get this:

apt install libdrm2 kde-standard
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
kde-standard : Depends: juk (>= 4:16.04.0) but it is not going to be installed
Depends: kate (>= 4:16.04.0) but it is not going to be installed
Depends: kde-plasma-desktop (>= 5:92) but it is not going to be installed
Depends: kopete (>= 4:16.04.0) but it is not going to be installed
Depends: okular (>= 4:16.04.0) but it is not going to be installed
Depends: plasma-pa (>= 5.8) but it is not going to be installed or
kmix (>= 4:16.04.0) but it is not going to be installed
Depends: plasma-wallpapers-addons (>= 4:5.8) but it is not going to be installed
Depends: plasma-widgets-addons (>= 4:5.8) but it is not going to be installed
Depends: sweeper (>= 4:16.04.0) but it is not going to be installed
Recommends: konq-plugins (>= 4:16.04.0) but it is not going to be installed
Recommends: plasma-nm (>= 4:5.8) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.


This is for Debian 9, stable. I never installed unstable or testing packages.

Now if I install each one of this works, BUT all dependencies of that package then get listed. It looks like I will have to mention EACH and EVERY package explicitly to install it? Why is this, I don't get it.

My sources:

cat /etc/apt/sources.list
#

deb http://deb.debian.org/debian stretch main contrib non-free
deb-src http://deb.debian.org/debian stretch main contrib non-free

deb http://deb.debian.org/debian-security/ stretch/updates main contrib non-free
deb-src http://deb.debian.org/debian-security/ stretch/updates main contrib non-free

deb http://deb.debian.org/debian stretch-updates main contrib non-free
deb-src http://deb.debian.org/debian stretch-updates main contrib non-free

deb http://ftp.uni-kl.de/debian-multimedia/ stable main
deb-src http://ftp.uni-kl.de/debian-multimedia/ stable main

deb http://deb.debian.org/debian stretch-backports main

I can uncomment the backports and multimedia repos and it does not make any difference at all.
These are the official debian repos, I just make sure of that.

What is going on here? Why is it refusing to install any dependencies unless I mention them explicitly?

Is there a way to let it spit out a full list of dependencies, all the way down so I can plug them in manually?

Do you have any other sources in your /etc/apt/sources.list.d/?

Offhand, I'd bet some package from backports got upgraded by something and is now preventing it from installing. But that's just because that's happened to me like 5 times, no guarantees that's it.

No, there are no other sources. I have to solve this, because if I shut down the system, there will be no coming back. If I get into the system via rescue, it will be exactly the same, no way to get the system back.
It is like the dpkg database is broken or something, I have never seen something like this.

I don't have another system that I can use, I'm currently homeless and this is pretty scary to be looking at an abyss.

The craziest thing is that it did not even ask me to go ahead, it just removed it all, no conformation, nothing. I would have paused and aborted otherwise of course.

So, here's how I'd deal with this. Obviously, there's some risk to doing it this way, but it has a really good chance of succeeding and fixing whatever got upgraded:

I'd create an /etc/apt/prefrerences.d/stretch.pref file, and in that file

apt update && apt install kde-standard

By setting stretch & stable (which are the same thing, but sometimes don't sync properly) to >1000 priority, it will actually allow it to DOWNGRADE any files that have been upgraded by other packages in order to install the file.

This is in no way the debian-proper way to do this, however having found myself in this issue multiple times in the past, I've had very good success at it. If you do this and it works, be sure to remove the preferences file after you finish as it can make it impossible to install from backports in the future.

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Keep adding the packages it complains about to the command line. Starting with the kde-plasma-desktop that should bring in almost all the missing packages it complains about right now as it should install all of kde which is what it is complaining about. BTW the next time you use the apt to do anything put the -s in there for simulation of the action to be taken. It will show you what it will do then once you are satisfied with the results then remove the -s for it to actually do something.

1 members found this post helpful.

I made some progress. Looks like that you were correct, it got some packages from backports. Normally it is not supposed to just use backports, only when
-t stretch-backports is specified in apt.
So now I tried
apt install -t stretch-backports kde-standard
and that works. WHEW....
It is installing.

By the way, installing all the packages by hand is impossible there are thousands of dependencies, a truly impossible task: every time you paste another one 5 more dependencies pop up.
Now it seems to be working again, for some reason the backports are pinned, but not, because otherwise it would not have replaced so much of kde with the bpo version.
Note to self: DON'T BE SUCH A STUPID ASS AND HAVE CURRENT BACKUP OF MY SYSTEM AT HAND (the backup I have is incomplete, the system is super solid and I never needed it before, well, here is me learning)

Wow, that was a scare. Maybe this can help somebody that runs into the same problem.

The pinning was very useful by the way, I was able to roll back everything to Stretch / Stable from backports, it was giving grief when installing things.
And good to report, I got a full system backup now. ;-)

Consider installing TimeShift and using it to create regular system snapshots to which you can roll back if situations like this occur.

Thanks, will check out timeshift, I can always use better tools. I know backintime, how does timeshift compare to that?

Could well have been the debian-multimedia repo - there are a few incompatibilities with some stock packages.

Also, I would strongly recommend replacing all “stable” entries with “stretch” as buster release is approaching and surprise upgrades rarely go well.

‘aptitude why-not package’ will answer your original query (probably need to install aptitude first now).

Bollocks.

Thanks for that tip, I always do that. I know the fine difference between stable and the release name, never had to make that mistake. But I do updates manually anyway, I would probably get suspicious if suddenly it wants to update the whole system all at once and I see the release name buster pop up in the package names ;-)
I did not even know how far buster was.