Live migrating Ubuntu to Debian - introduction

I was a long time Debian user before I switched to Ubuntu in 2005. I always liked Debian for its stability, wide choice of software and superior package management. However, at this point Debian release cycle, always long and unpredictable, got even longer than usual. A stable or even testing version of Debian meant seriously outdated software, not to mention poor hardware support. With Ubuntu, my laptop finally got a decent power management out of the box. There were other improvements, like NetworkManager and a general focus on ease of use. Plus, being a Debian derivative, Ubuntu inherited many good traits of its ancestor. It was a good choice than and for a few following years.
Then something began to break. There were some controversial design choices, but even worse was declining quality. For the last few releases I had to deal with numerous bugs, some serious, most minor but annoying. 9.10 was pretty bad, but a last normal release before LTS is always a playground for new technology. But 10.4 is even worse and it's supposed to be a Long Term Support release! Everyday I install a few updates (yes, I'm happy the bugs are getting fixed, but there shouldn't be that many in the first place) and yet my machine is still unstable. My box would sometimes lock up or get a load average of 15 for no appearent reason.
In the meantime, Debian release cycle got shorter and predictable. Many Ubuntu usability improvements were merged back upstream. Some widely reported features are not useful at all for me: I don't need Ubuntu One, I use unison on my own server; I don't need Software Center cause I prefer Aptitude etc. I decided it's time to move back. Clean install would be an obvious choice, but I decided to migrate a live system instead. There were some issues, but it worked. Did I mention that Debian has a great package manager?
If you want to know how to migrate from Ubuntu do Debian, stay tuned for the next part (update: it's here). In the meantime, you can read my post on downgrading Ubuntu. If it seems complicated or dangerous, be warned that migration to Debian is quite harder.

Howto: disable eCryptFS

Encrypting your disk is usually a good idea and eCryptFS (aka Ubuntu Encrypted Home) clearly has some advantages over the competitors. It's also easy to implement on an existing system. But, if for some reason you want to decrypt your home directory, you won't get a one-click solution. The process is quite simple if you feel comfortable working with command line.


I'll use /home/igor as an example, replace it with your home directory.


1. Prepare another user account.

Either unlock your root account (sudo passwd root) or create another user account and let it use sudo. I've chosen the first option because a root account is useful for recovery if anything goes wrong.


2. Logout from your desktop environment, switch to console (Alt-Ctrl-F1)


3. Login as root or as another user.

This is critical - you can't be logged in on your regular account. Type 'mount' and see if it shows a line similar to this one:

/home/igor/.Private on /home/igor type ecryptfs (ecryptfs_sig=...)

It shouldn't be present. If it is, try 'umount /home/igor'. If it fails, you probably have a session still loged on or one of your applications is still running. If you can't find it, try rebooting and switching to console without ever logging in.


4. Edit file /home/.ecryptfs/igor/.ecryptfs/Private.mnt

Change the line /home/igor to /home/igor/Private


5. Create Private directory and make it belong to your regular account

mkdir /home/igor/Private
chown igor.igor /home/igor/Private

6. Reboot the computer

After the reboot, everything that was in /igor/home directory, is now in /igor/home/Private. There's only one step left.


7. Move the files

Switch to console, login with your regular account. Move the files:

shopt -s dotglob
mv Private/* .

First command is very important - it'll make sure that files beginning with dot will also be moved. Second one ends with dot - don't miss it!


8. Uninstall eCryptFS or leave it as it is

At this point, eCryptFS encrypts your ~/Private directory instead of your home. You can leave it for confidential files, or if you want to get rid of eCryptFS, do:

sudo apt-get remove ecryptfs-utils