resizing existing partitions?

Jukas · 09-19-2006, 07:54 PM

I have a Debian machine with a 250gb hdd in it that I really need to resize the partition on an active ext3 filesystem.

Code:

# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/hda1             4.6G  932M  3.5G  21% /
tmpfs                1010M     0 1010M   0% /dev/shm
/dev/hda9             102G  129M   97G   1% /backup
/dev/hda8              92G  129M   87G   1% /home
/dev/hda7             669M   17M  618M   3% /tmp
/dev/hda5              14G  1.1G   12G   9% /usr
/dev/hda6              14G  566M   13G   5% /var
tmpfs                  10M   52K   10M   1% /dev

This box is now going to be used as a mail server, which means it's goign to generate a lot of logs. I need to take some of the space from either the hda8 or hda9 partition and increase the size of the hda6 partion.

Is it possible to do this without having to reinstall the entire server from scratch?

luis14 · 09-19-2006, 08:50 PM

I have used gparted live cd and qparted in the kanotix live cd to resize partitions. Both work well and allow you to view changes graphically before commiting. If I understand your partition scheme I believe you could delete hda7, shrink hda8, and in the freed up space make a new hda7 and grow hda6 to fill the balance.

basileus · 09-20-2006, 02:43 PM

I usually do resize partitions on the fly like this (there might be typos in here, please use common sense

Copy the data to another partition: "cp -a /var /usr/var". Note that the -a switch is mandatory, otherwise you'll screw up everything

Unmount the partition (umount /var)

Remove the old mountpoint (rm -rf /var)

Link the new location to the old mountpoint (ln -s /usr/var /var): this way system does not even know that /var was gone.

Do the necessary resizing of the (unused) partition with "cfdisk", "fdisk" or whatever.

Mount the newly created partition to some other directory (mkdir /newvar;mount -t ext3 /dev/hdaX /newvar)

Copy the data to the new partition (cp -a /usr/var/* /newvar)

Unmount the new partition (umount /newvar)

Remove the symbolic link (rm /var)

Rename the new partition (mv /newvar /var)

Edit /etc/fstab and mount the new partition (mount /var)

Gosh... that seems quite complicated

. But I've moved all my partitions once or twice in above manner and I haven't experienced any problems so far. Actually once you get the idea this procedure is rather easy, even though by no means a perfect solution.

If you can, resize the partion on the fly without all this fuss. Just take backups with the "cp -a" first, just in case.

Zmyrgel · 09-20-2006, 11:11 PM

I've used similar process as above and currently I'm using the lvm-partitions as they make the process nice and easy