How to completely (all the packages were installed) remove or disable the tasksel desktop environment?

Question

I accidentally installed desktop environment at the debian install. Now I'm trying to remove it but no chance: tasksel remove desktop changed only i to u if tasksel --list-tasks.

sudo apt-get remove task-desktop doesn't work neither: no output at all.

I even cannot see what task-desktop package has as meta-package in there.

I just want to get a server debian, not a desktop.

Solution

What I would do, in preference order:

1. Reboot and reinstall my server using PXE + preseed. This way you have a reproducible method of installing without error prone human intervention. The time spent setting this up pays off the second time you use it.

2. If reinstallation is off the table:

   a. I'd try to find out what packages were installed by the task selection, starting by listing available selections:

   $ tasksel --list-tasks
   u desktop       Debian desktop environment
   u web-server    Web server
   u print-server  Print server
   u database-server       SQL database
   u dns-server    DNS Server
   u file-server   File server
   u mail-server   Mail server
   u ssh-server    SSH server
   u laptop        Laptop
   

   b. Followed by listing the specific selection:

   $ tasksel --task-packages desktop
   task-desktop
   

   c. Show the package metadata to find out its dependencies:

   $ aptitude show task-desktop
   Package: task-desktop
   State: not installed
   Version: 3.16
   Priority: optional
   Section: tasks
   Maintainer: Debian Install System Team <[email protected]>
   Architecture: all
   Uncompressed Size: 21.5 k
   Depends: tasksel, xorg, xserver-xorg-video-all, xserver-xorg-input-all, desktop-base, menu
   Recommends: task-gnome-desktop | task-kde-desktop | task-lxde-desktop | task-xfce-desktop, xdg-utils, avahi-daemon, libnss-mdns, anacron, libgl1-mesa-dri, eject, iw, alsa-utils, alsa-base, pm-utils
   Description: Debian desktop environment
    This task package is used to install the Debian desktop.
   

   d. You can repeat the last step for each and everyone of the dependencies, or use another tool to find that information directly:

   $ apt-cache depends task-desktop
   task-desktop
     Depends: tasksel
     Depends: xorg
     Depends: xserver-xorg-video-all
     Depends: xserver-xorg-input-all
     Depends: desktop-base
     Depends: menu
    |Recommends: task-gnome-desktop
    |Recommends: task-kde-desktop
    |Recommends: task-lxde-desktop
     Recommends: task-xfce-desktop
     Recommends: xdg-utils
     Recommends: avahi-daemon
     Recommends: libnss-mdns
     Recommends: anacron
     Recommends: libgl1-mesa-dri
     Recommends: eject
     Recommends: iw
     Recommends: alsa-utils
     Recommends: alsa-base
     Recommends: pm-utils
   

   e. There are tools to list forward and reverse dependencies, with output filtering options:

   $ apt-rdepends -r task-desktop --state-follow=Installed
   Reading package lists... Done
   Building dependency tree
   Reading state information... Done
   task-desktop
     Reverse Depends: task-gnome-desktop (3.16)
     Reverse Depends: task-kde-desktop (3.16)
     Reverse Depends: task-lxde-desktop (3.16)
     Reverse Depends: task-xfce-desktop (3.16)
   
   $ apt-rdepends task-desktop --state-follow=Installed
   Reading package lists... Done
   Building dependency tree
   Reading state information... Done
   task-desktop
     Depends: desktop-base
     Depends: menu
     Depends: tasksel
     Depends: xorg
     Depends: xserver-xorg-input-all
     Depends: xserver-xorg-video-all
   menu
     Depends: dpkg (>= 1.15.4)
     Depends: install-info
     Depends: libc6 (>= 2.2.5)
     Depends: libgcc1 (>= 1:4.1.1)
     Depends: libstdc++6 (>= 4.6)
   dpkg
     PreDepends: libbz2-1.0
     PreDepends: libc6 (>= 2.11)
     PreDepends: liblzma5 (>= 5.1.1alpha+20120614)
     PreDepends: libselinux1 (>= 1.32)
     PreDepends: tar (>= 1.23)
     PreDepends: zlib1g (>= 1:1.1.4)
   

   f. At this point, you can start uninstalling stuff, using tools like orphaner to ensure you leave nothing behind, or start looking at option 1. with better eyes.