Prompt temporary move /var/cache/apt to other partition for distribution upgrade

[Pander]

Binary package hint: update-manager

In case of doing a distribution release upgrade (e.g. Feisty to Gutsy) it can occur that the root partition / (containing at least /var and /usr) does not have enough free disk space. Now the distribution upgrade cannot take place. Only advanced users can move /var/cache/apt to another partition and create a link in order to be able to do this distribution upgrade.

I would like to suggest to offer this automatically when there is not enough free disk space when doing a distribution release upgrade. The user can be prompted to indicate what partition to temporarily use for this upgrade. The update manager can then move /var/cache/apt/ to e.g. /home/DO-NOT-DELETE-TEMPORARY-var-cache-apt-2007-10-09-13:38:15 and create a link /var/cache/apt pointing to this directory. Then continue performing the upgrade and at the end, after doing apt-get clean, removing the link and moving this directory back to /var/cache/apt.

Of course extra checks should be build in to detect and restore any interrupted upgrades leaving these kind of directories in other partitions and a link at /var/cache/apt.

Implementing this functionality will allow many more (non-advanced) users to be able to do a distribution release upgrade (like Feisty to Gutsy) without having a root partition being roughly three times oversized. I would consider implementing this before releasing the stable version of Gutsy.

[Pander (pander)]

see also http://brainstorm.ubuntu.com/idea/13235/

[Rolf Leggewie (r0lf)]

I believe giving the user clear instructions what to do would be enough (bug 523004)

[Pander (pander)]

Thanks for the feedback. I agree that clear instructions and some relevant data concerning file systems would help the user a lot. Just make sure these checks are done before downloading an entire version upgrade.