apt-get autoremove dangerous?

Question

I was compiling a tool called Rejoystick so I installed a few packages and dependencies. But now I don't need it any more so I removed those packages. Running apt-get shows that I have some packages that are automatically installed and are no longer needed.

But I have a bad experience with apt-get autoremove. It broke my desktop environment when I uninstalled wine some time ago. Luckily, I had a clonezilla partition backup then, but this time, I don't have a backup. So I'm cautious. Running apt-get shows these packages are orphaned

  gir1.2-gtk-2.0 libasound2-dev libavahi-client-dev libavahi-common-dev
  libcaca-dev libcairo-script-interpreter2 libdbus-1-dev libdrm-dev
  libexpat1-dev libfontconfig1-dev libfreetype6-dev libgl1-mesa-dev
  libglu1-mesa-dev libharfbuzz-dev libharfbuzz-gobject0 libice-dev
  libpcre3-dev libpcrecpp0 libpixman-1-dev libpng12-dev libpthread-stubs0-dev
  libslang2-dev libsm-dev libx11-dev libx11-doc libx11-xcb-dev libxau-dev
  libxcb-dri2-0-dev libxcb-dri3-dev libxcb-glx0-dev libxcb-present-dev
  libxcb-randr0-dev libxcb-render0-dev libxcb-shape0-dev libxcb-shm0-dev
  libxcb-sync-dev libxcb-xfixes0-dev libxcb1-dev libxcomposite-dev
  libxcursor-dev libxdamage-dev libxdmcp-dev libxext-dev libxfixes-dev
  libxft-dev libxi-dev libxinerama-dev libxrandr-dev libxrender-dev
  libxshmfence-dev libxxf86vm-dev mesa-common-dev x11proto-composite-dev
  x11proto-core-dev x11proto-damage-dev x11proto-dri2-dev x11proto-fixes-dev
  x11proto-gl-dev x11proto-input-dev x11proto-kb-dev x11proto-randr-dev
  x11proto-record-dev x11proto-render-dev x11proto-xext-dev
  x11proto-xf86vidmode-dev x11proto-xinerama-dev xorg-sgml-doctools xtrans-dev
  zlib1g-dev

I'm not sure if I should run apt-get autoremove. I was searching details related to each of these packages so that I can understand which ones are needed but they all seem important e.g.

gir1.2-gtk-2.0

I have Cinnamon, GNOME and Unity installed, I think apt-get autoremove will break something. Any help will be appreciated.

Thanks for reading.

Answer 1

As others mentioned, autoremove should be safe, but then again, you said that you have bad experiences, and I also remember autoremove removing some stuff that should not be removed.

It seems like autoremove can have problems with some meta-packages. Say you installed the gnome meta-package for the entire gnome-desktop (or it was installed when setting up the system), which also includes programs like evolution and lots of games, which you might want to remove, because you are using thunderbird and do not want to have those games and the like. This requires you to also remove the gnome meta-package, since it depends on all those packages. But this will make all the other packages that were installed as dependencies of gnome "auto-removeable", including e.g. gnome-shell, which you most likely want to keep if you want to continue using that desktop.

So it's always a good idea to check the packages recommended for auto-removal. If you are using a graphical package manager like synaptic, you can easily do so and uncheck the "automatically installed" flag from packages you want to keep (like gnome-shell in the above example). This will also remove all the packages those depend on from the auto-removeable list, so you might only have to "fix" a few of those, and not all.

Still, it should not remove anything that's really essential to your system, so even if you accidentally removed e.g. your desktop, you can still boot and log into your system and revert those changes using the command line.

---

Update: Recently, after a dist upgrade (Debian), autoremove actually removed something related to hard disc encryption (still not sure what exactly, probably related to the issue described here), causing my system to be unable to decrypt the hard disc and to boot with the latest Kernel. Luckily, it still worked with an older Kernel that was still installed and I could re-install all that was previously autoremoved, otherwise my system would have been wrecked, including my data.

I don't think there is a "undo last changes" option in apt and friends. In synaptic there is a menu option to see the last changes (File -> History; seems to just show some log files, although I could not find the logs themselves; also, I am not sure if this only lists changes made in Synaptic or also e.g. in apt etc.), so I copied the names of all the packages I autoremoved since the last successful reboot (luckily, I reboot daily) from those logs and re-installed them, then rebooted.

Answer 2

Surprising to see no one has yet mentioned the --dry-run and equivalent options:

From apt-get's man page:

-s, --simulate, --just-print, --dry-run, --recon, --no-act
No action. Perform a simulation of events that would occur but do not actually change the system.

Configuration Item: APT::Get::Simulate.
Simulate prints out a series of lines, each one representing an rpm operation: Configure (Conf), Remove (Remv), Unpack (Inst).

This option seems to work with both the apt and apt-get commands.

Example output:

sudo apt-get autoremove --dry-run
[...]
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages will be REMOVED:
  linux-headers-5.8.0-36-generic linux-hwe-5.8-headers-5.8.0-36 linux-image-5.8.0-36-generic
  linux-modules-5.8.0-36-generic linux-modules-extra-5.8.0-36-generic
0 upgraded, 0 newly installed, 5 to remove and 13 not upgraded.
Remv linux-headers-5.8.0-36-generic [5.8.0-36.40~20.04.1]
Remv linux-hwe-5.8-headers-5.8.0-36 [5.8.0-36.40~20.04.1]
Remv linux-modules-extra-5.8.0-36-generic [5.8.0-36.40~20.04.1]
Remv linux-image-5.8.0-36-generic [5.8.0-36.40~20.04.1]
Remv linux-modules-5.8.0-36-generic [5.8.0-36.40~20.04.1]

So I suggest one can run autoremove with the --dry-run option, study the output with a cool head, and decide what to do based on that.

An additional observation: if one runs autoremove regularly, then the autoremovable packages do not pile up, and thus it remains more doable to oversee and evaluate the output of each dry-run.

Answer 3

Usually it should be save to run autoremove. But in case of packaging bugs essential packages might get removed. I made my system unbootable by running an apt autoremove, so I highly recommend quickly looking through the packages which are to be removed.

Edit: This answer describes how apt autoremove broke my system and how necessary steps to repair it.

Answer 4

apt-get remove can ABSOLUTELY destroy your system. It's happened to me twice and I can repeat it (on a Debian-based distro); both times on a vbox, so no big whoop. I watched it remove my entire XFCE installation.

Answer 5

It should be perfectly safe to run sudo apt-get autoremove This should only remove packages that are not in use or needed any longer. If its a necessary package that would "break" your system if removed it shouldn't remove it.

Answer 6

From man apt-get:

 autoremove
       autoremove is used to remove packages that were automatically
       installed to satisfy dependencies for other packages and are now no
       longer needed. 

Have you installed other packages (and their dependencies), and subsequently removed the packages?

Answer 7

Firstly, you can try finding out what these packages are there for. Using apt show <package> is a good way. Doing this may lead to understanding like '*-dev' packages are mostly development files that have no impact on normal operation. In many cases they have been installed for compile work.

Secondly, looking into the list you may note there is one exception named gir-gtk-2.0. Apt tells it is for gnome-2.0 gui, which in your case could be useless.

In short, you'd better exlopre a little before making a decision. This question highly depends on the specific packages to deal with, rather than on some general principal as some suggest.