Re: repartitioning without losing data

["Rodolfo J. Paiz" <rpaiz simpaticus com>]

At 22:22 1/1/2004, you wrote:
> Easy.
>
> 1) Reboot to single-user mode.
> 2) umount /home (if already mounted)
> 3) mkdir /home
> 4) mkdir /mnt/home
> 5) mount -t<type> /dev/<old /home partition> /mnt/home
> 6) mv /mnt/home/* /home/
> 7) umount /mnt/home
> 8) Use parted to repartition and format your partitions (man parted)
> 9) mount -t<type> /dev/<new /home partition> /mnt/home
> 10) mv /home /mnt/home/
> 11) umount /mnt/home
> 12) rmdir /home
> 13) Edit /etc/fstab as necessary
> 14) Reboot
>
> Sounds worse than it is.  It's just a lot of little steps.  I haven't
> used parted much, so I'd suggest testing it on another drive first, just
> so you get comfortable with it.
>
> P.S.  Sean/Rodolfo/Ed, if I've forgotten anything, please speak up.  I
> need sleep.  ;-)

Heh... I was heading for bed myself when I saw this. Specifically 
disregarded it when I saw your answer since I knew the bases would be 
properly covered (the post coming from you and all), but was forced to come 
back when I noticed the postscript. Anyway, no... you haven't missed 
anything, as usual. I would change the following due to personal preference:

        6) I think "rsync -avP /mnt/home/* /home/" be neater. Ownership, 
permissions, creation and modification times will be more carefully kept 
intact. And overall, I just trust rsync more than mv, since that's what I 
use regularly to mirror 90GB of data from one place to another. And I get a 
nice display of what's going on so I don't see a blank screen and chew my 
nails off while I wonder if it's working or destroying my data. <grin> Just 
personal preference, really.

        10) See #6.

Note, also, that the user can get confused when doing this and wonder where 
the data is coming from or going to, with all those "home" directories 
running around. It might be easier to follow if the files were moved in 
this order:

        1. From old /home partition
        2. To /homebackup
        3. To new /home partition

This seems like a little less work, since then what you have is:

        1. Reboot to single-user mode.
        2. "rsync -avP /home /homebackup"
        3. CHECK THE CONTENTS OF /HOMEBACKUP!!!
        4. "umount /home"
        5. Use parted to:
                5a. Delete old /home.
                5b. Resize /.
                5c. Create new /home.
        6. Edit /etc/fstab to point /home to the new partition.
        7. "mount /home"
        8. "rsync -avP /homebackup /home"
        9. CHECK THE CONTENTS OF /HOME!!!
        10. "rm -rf /homebackup"
        11. Reboot.

Remarkably similar, and in fact I reread your sequence to make sure I 
hadn't forgotten anything in noting mine. This is just (to my one-track 
mind) slightly less prone to confusion for a newbie.

For the OP: rsync and mv are both very sensitive about trailing slashes. 
Using "/home" means the home directory itself, and in some cases also its 
contents. Using "/home/" with a trailing slash means the contents of /home, 
equivalent to /home/*. So to illustrate:

"rsync -av /home /homebackup" will copy over the home directory and its 
contents to the / directory under the name /homebackup. You end up with 
/home and /homebackup with identical contents. But if you add in one slash, 
as in "rsync -av /home /homebackup/" you'll end up with /homebackup/home/* 
(the home directory and its contents copied to inside the homebackup 
directory, not to it.)

G'night!


--
Rodolfo J. Paiz
rpaiz simpaticus com
http://www.simpaticus.com