This part is automatic and comparable to the Gandi AI procedure

This procedure applies to data disks, without partitions.

First of all, it is necessary to verify the file system, to correct any existing errors on the disk, so that it can then be marked as "clean" and thus resized. The following example is based on the disk /dev/xvdb:

# umount /dev/xvdb
# e2fsck -f /dev/xvdb
e2fsck 1.40.2 (12-Jul-2007)
Passe 1 : vérification des i-noeuds, des blocs et des tailles
Passe 2 : vérification de la structure des répertoires
Passe 3 : vérification de la connectivité des répertoires
Passe 4 : vérification des compteurs de référence
Passe 5 : vérification de l'information du sommaire de groupe
disque2: 11/3014656 files (9.1% non-contiguous), 134435/6029312 blocks

If e2fsck indicates that there are problems, it is necessary to correct them before continuing.

Once the disk has been verified, and any errors corrected, it is possible to change the size of the file system so that it corresponds to the size of the disk:

# resize2fs /dev/xvdb
Resizing the filesystem on /dev/xvdb to 6815744 (4k) blocks.
Le système de fichiers /dev/xvdb a maintenant une taille de 6815744 blocs.

Resizing a system disk is a delicate and risky procedure. In the event that an error occurs during the deletion and the creation of partitions, it is possible to lose the system disk. Please, therefore, proceed with extreme care.

First of all, it is imperative to deactivate the Swap, as the partition that contains it will be deleted.

# swapoff /dev/xvda2

Next, you will need to launch an fdisk to change the partitions. There are two partitions, the system partition and the one used for swap. The two will be deleted, the system partition will be enlarged.

# fdisk /dev/xvda

The number of cylinders for this disk is set to 5221.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
   (e.g., DOS FDISK, OS/2 FDISK)

Command (m for help): p

Disk /dev/xvda: 42.9 GB, 42949672960 bytes
255 heads, 63 sectors/track, 5221 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

    Device Boot      Start         End      Blocks   Id  System
/dev/xvda1               1         312     2506108+  83  Linux
/dev/xvda2             313         391      634567+  82  Linux swap / Solaris

The display is changed to sectors:

Command (m for help): u
Changing display/entry units to sectors

The swap is deleted:

Command (m for help): d
Partition number (1-4): 2

Command (m for help): p

Disk /dev/xvda: 42.9 GB, 42949672960 bytes
255 heads, 63 sectors/track, 5221 cylinders, total 83886080 sectors
Units = sectors of 1 * 512 = 512 bytes

    Device Boot      Start         End      Blocks   Id  System
/dev/xvda1              63     5012279     2506108+  83  Linux

Next, the system partition is deleted:

Command (m for help): d
Selected partition 1

Now that the two partitions have been deleted, they need to be created again. First, re-create the system partition with the correct size. In our example, it is 40 GB.

Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
p
Partition number (1-4): 1
First sector (63-83886079, default 63):
Using default value 63
Last sector or +size or +sizeM or +sizeK (63-83886079, default 83886079): +40G

Command (m for help): p

Disk /dev/xvda: 42.9 GB, 42949672960 bytes
255 heads, 63 sectors/track, 5221 cylinders, total 83886080 sectors
Units = sectors of 1 * 512 = 512 bytes

    Device Boot      Start         End      Blocks   Id  System
/dev/xvda1              63    78125063    39062500+  83  Linux

Next, it is necessary to recreate the Swap partition.

Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
p
Partition number (1-4): 2
First sector (78125064-83886079, default 78125064):
Using default value 78125064
Last sector or +size or +sizeM or +sizeK (78125064-83886079, default 83886079):
Using default value 83886079

Then, give the swap partition the type, "Linux swap":

Command (m for help): t
Partition number (1-4): 2
Hex code (type L to list codes): 82
Changed system type of partition 2 to 82 (Linux swap / Solaris)

Command (m for help): p

Disk /dev/xvda: 42.9 GB, 42949672960 bytes
255 heads, 63 sectors/track, 5221 cylinders, total 83886080 sectors
Units = sectors of 1 * 512 = 512 bytes

    Device Boot      Start         End      Blocks   Id  System
/dev/xvda1              63    78125063    39062500+  83  Linux
/dev/xvda2        78125064    83886079     2880508   82  Linux swap / Solaris

Finally, save all the modifications

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 16: Périphérique ou ressource occupé.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.

You will eventually need to force the fsck on rebooting, according to the distribution, and reboot:

# touch /forcefsck
# reboot

If the fsck did not occur during the boot, it will be necessary to perform it. For this, you will first need to perform a "lsof" and "kill" any processes that have w/u in / :

# mount -o remount,ro /
# fsck -f /dev/xvda1
fsck 1.40-WIP (14-Nov-2006)
e2fsck 1.40-WIP (14-Nov-2006)
Passe 1 : vérification des i-noeuds, des blocs et des tailles
Passe 2 : vérification de la structure des répertoires
Passe 3 : vérification de la connectivité des répertoires
Passe 4 : vérification des compteurs de référence
Passe 5 : vérification de l'information du sommaire de groupe
DEBIAN4: 20503/313600 files (2.2% non-contiguous), 156236/626527 blocks

If the corrections occurred during the fsck it will be necessary to reboot. Otherwise, all that remains is resizing the file system.

For this, we use resize2fs:

# resize2fs /dev/xvda1
resize2fs 1.40-WIP (14-Nov-2006)
Filesystem at /dev/xvda1 is mounted on /; on-line resizing required
old desc_blocks = 1, new_desc_blocks = 3
Performing an on-line resize of /dev/xvda1 to 9765625 (4k) blocks.

Le système de fichiers /dev/xvda1 a maintenant une taille de 9765625 blocs.

It is possible to check the size of the disk with the df command:

# df -h
Sys. de fich.         Tail. Occ. Disp. %Occ. Monté sur
/dev/xvda1             37G  576M   36G   2% /