Uninstall KDM in KDE 4.9.3

[infoholico]

Hello people, I have Kubuntu 12.10 with KDE 4.9.3 but when installing an error ocurred and the configuration screen closed, now I have LightDM and KDM, how could I do to securely remove KDM? I hate KDM, it does not have the correct resolution for my monitor.

[vw72]

Try opening a terminal and entering:
sudo dpkg-reconfigure kdm

And then select LightDM from there. That won't uninstall KDM, but the next time you reboot, LightDM should be your login manager.

After you successfully reboot and login with LightDM, you can always open a terminal and sudo apt-get remove kdm but you should check and see if it is also going to remove anything else that might be dependent on it that you might want. It doesn't hurt to have both installed, the system can only use one or the other.

[Snowhog]

KDM can't be uninstalled without removing a significant portion of your installation. LightDM depends on KDM.

[vw72]

KDM can't be uninstalled without removing a significant portion of your installation. LightDM depends on KDM.

Didn't know that, but the sudo reconfigure kdm should still allow lightdm to be selected!

[infoholico]

Thanks, I solved it tonight, as vw72 suggested I used sudo dpkg-reconfigure but lightdm instead of kdm:

sudo dpkg-reconfigure lightdm

Then I uninstalled kdm because it was pointless to have both,

sudo apt-get remove kdm

And problem solved thanks a lot.

[claydoh]

KDM can't be uninstalled without removing a significant portion of your installation. LightDM depends on KDM.

No, they are entirely separate entities actually

[Snowhog]

No, they are entirely separate entities actually

I was just a tad hesitant when I posted my comment. Yours jogged my memory a bit.

If you only have KDM installed, and want to only have LightDM, you must install LightDM first, removing KDM (if you truly don't want it on your system) afterwards. If you remove KDM when you don't have any other DE installed, a lot of your system goes bye-bye with it.

[claydoh]

You do not need a login manager at all if you don't want one KDM is only connected to the meta-package kubuntu-desktop so removing it does not take away anything from your system

claydoh@claydoh-Latitude-D630:~$ sudo apt-get remove kdm
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
kdm kubuntu-desktop
0 upgraded, 0 newly installed, 2 to remove and 0 not upgraded.
After this operation, 2,833 kB disk space will be freed.
Do you want to continue [Y/n]?

claydoh@claydoh-Latitude-D630:~$ lsb_release -a
Distributor ID: Ubuntu
Description: Ubuntu 12.04.1 LTS
Release: 12.04
Codename: precise

[Snowhog]

Well, I guess it's time to refill "Sherlock Tux's" pipe, as obviously, he's "sucking air" on this.

[james147]

You do not need a login manager at all if you don't want one KDM is only connected to the meta-package kubuntu-desktop so removing it does not take away anything from your system

But removing kubuntu-desktop can cause major problems when upgrading to the next version of kubuntu.

[luckyone]

Easier to keep both, or even have gdm available also. I've messed up one and had to switch to the other so I (a simple User) could repair things.

[SteveRiley]

You do not need a login manager at all if you don't want one KDM is only connected to the meta-package kubuntu-desktop so removing it does not take away anything from your system

Changed in 12.10. The dependency on KDM is gone:

steve@t520:~$ [B]apt-cache rdepends kdm[/B]
kdm
Reverse Depends:
  kdm:i386
  kde-workspace
  kdm:i386
  kde-workspace
  kdm:i386
  plymouth:i386
  kdm-gdmcompat
  kdm-gdmcompat
  kde-workspace
  kde-wallpapers
  kde-wallpapers
  kde-plasma-netbook
  kde-plasma-desktop
  plymouth
  numlockx