move usr

[Linux Lover II]

Is it possible to move the usr to another folder/partition?

Thanks in advance!

[srs5694]

It's not practical to rename /usr to another name; too much stuff is coded to look in there.

You can, however, move the contents to another (empty) partition:



Prepare the destination partition. (I'll assume you know how to do this.) Let's call it /dev/sdb1; change as necessary in the following commands.
Type "sudo mount /dev/sdb1 /mnt" (or use another mount point).
Type "cd /usr".
Type "sudo tar cpf - ./ | (cd /mnt; sudo tar xvf -)". This command will take a while to complete. You'll see the filenames as they're copied.
Inspect the contents of /mnt and /usr. They should be identical, with the possible exception of the lost+found directory (which is present on some filesystems but not others).
Shut down and reboot into an emergency disc. Open a shell.
Mount your root (/) filesystem somewhere convenient in the emergency disc's system. Let's say it's /mnt/foo. The following commands may need a "sudo" added to their starts, depending on the emergency system you use.
Type "mv /mnt/foo/usr /mnt/foo/usr-old"
Type "mkdir /mnt/foo/usr"
Edit /mnt/foo/etc/fstab and add an entry for your new partition. It might look like "/dev/sdb1 /usr ext3 defaults 0 2", but you should adjust the entry as necessary. You might need to change the filesystem type or want to use different mount options, for instance. You can also change /dev/sdb1 to a UUID specification (as Ubuntu uses on its automatically-created /etc/fstab entries). This isn't required, but it could make some automated administration tools behave more predictably.
Reboot.
If the system comes up and you can log in, chances are everything is fine. Still, you should give it a thorough test to be sure everything in /usr is working right. I'd do this by using the system normally for a day or two.
Once you're satisfied everything's working, delete /usr-old.



If the system doesn't reboot cleanly, then you'll have to reboot back into the emergency disc to figure out what went wrong. Maybe you've got permissions problems on /usr or not all of the files were copied correctly. Mistyping the tar commands can cause all sorts of problems. In a worst-case scenario, you can comment out your new /etc/fstab entry, delete the empty /usr directory, and rename /usr-old back to /usr to get back to a working system.