Comment 0 for bug 1415785

Please remove all references to the ltsp-client, ltsp-client-core, ltspfs, and ltspfsd packages from the update-manager sources, as update-manager currently removes those packages on dist-upgrades.

Please also SRU this to 12.04 and 14.04, I've seen dozens of LTSP installations break because of this.

Rationale:
Historically, the ltsp-client package had a preinst check that aborted its installation in normal systems (by checking for an /etc/ltsp_chroot file).

If someone managed to install it outside of an LTSP chroot, then dist-upgrades were broken there, and a workaround was introduced in update-manager 1:0.60 gutsy Tue, 24 Apr 2007 16:39:26 +0200.
This is mentioned in the update-manager changelog and in LP #109638.

But, since Ubuntu Precise, ltsp-client no longer has these restrictions (I'm an upstream LTSP developer) and it's even useful to have it installed in normal LTSP servers (see https://help.ubuntu.com/community/UbuntuLTSP/ltsp-pnp for more info).

Now the opposite problem arises: when there's need for `update-manager -dist-upgrade`, update-manager removes at least ltsp-client and ltspfsd, breaking LTSP installations.
See the attached update-manager screenshot.

Actual use case: a teacher is prompted for a normal update, where some packages need to be updated, and additionally some unrelated package is now obsolete and needs to be removed. In that case, update-manager starts a dist-upgrade (not to be confused with a release upgrade, it's normal maintenance, not e.g. upgrading from 12.04 to 14.04) and removes ltsp-client and ltspfsd. The LTSP server stops working and the teacher doesn't know why, he never even pressed the "expand" button in the update dialog to see that those packages were uninstalled.