Comment 31 for bug 106209

The one thing I don't understand about this bug is that Ted has said (e.g. in https://bugs.launchpad.net/ubuntu/+bug/106209/comments/20) that Ubuntu trashes swap UUIDs by running mkswap, but as far as I know this isn't true any more. Since Ubuntu 7.04, we don't just run mkswap; we extract the old UUID with dd, run mkswap, and reinsert the old UUID again. (The reason we run mkswap at all is that it turns out to be a lot faster than asking libparted to check whether the swap partition is valid.)

If we discount swap as a red herring - or at the very least a bug that's been fixed for some time, even if it still hangs around due to 6.06 and 6.10 - then there are two parts to this bug:

  1) Some component of partman, probably partman-target, should check before formatting whether any of the partitions you're formatting are referred to by /etc/fstab in any of the other filesystems on the system, and issue a warning that doing this will confuse those other installations. The suggestion to add an option to save the UUID and put it back after formatting is intriguing, though of course we can only do this for sure if we're still using the same filesystem.

  2) Arguably, partman-auto should not automatically mount filesystems that contain (say) /etc/fstab. I'm a little more sceptical about this, because I think we're going to be caught between a rock and a hard place. Let's say you're migrating from Red Hat to Ubuntu, and your Red Hat installation doesn't have a separate /home. In that case, it's convenient to be able to get at /home anyway, and certainly it feels inconsistent to have /home automounted only if it's on a separate partition. (Jerry may be happy to mount it by hand, but we added the automounting precisely because not everyone knew how to do that.) That said, I take Ted's point that there's no way to specify the difference between something that's in fstab for convenience and something that's there out of necessity, short perhaps of setting fs_passno to 0.

However ... the desktop has got better since we did all this automounting stuff originally. Nowadays you can go to Places -> Computer, double-click on the filesystem you want to use, enter your sudo password, et voilà. That wasn't the case in 5.10 when this was first implemented. Thus, perhaps it's no longer worth it, and I'm moving this bug over to partman-auto and targetting it to Hardy for further consideration.

If you still want the automounting done in the installer, then speak now or forever hold your peace ...