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July 20, 2010

Resizing an iSCSI Device

I'm trying to increase the size of an iSCSI device. On the LUN side, the provision size has been expanded already.
I expanded the size of this device from 15GB to 30GB.

I then rescanned the devices:

[root@ps-dev-nfs ~]# iscsiadm -m node --targetname iqn.2001-05.com.equallogic:0-8a0906-db7938c02-c6a994bda8a4a773-ps-dev-nfs -R
Rescanning session [sid: 1, target: iqn.2001-05.com.equallogic:0-8a0906-db7938c02-c6a994bda8a4a773-ps-dev-nfs, portal: 10.3.2.10,3260]
Rescanning session [sid: 2, target: iqn.2001-05.com.equallogic:0-8a0906-db7938c02-c6a994bda8a4a773-ps-dev-nfs, portal: 10.3.2.10,3260]

If I check the size of the devices (/dev/sdb, /dev/sdc and /dev/dm-0), I see them reflecting the new size:

[root@ps-dev-nfs ~]# fdisk -l

Disk /dev/sda: 64.3 GB, 64347963392 bytes
255 heads, 63 sectors/track, 7823 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sda1 * 1 5151 41375376 83 Linux
/dev/sda2 7195 7703 4088542+ 82 Linux swap / Solaris

Disk /dev/sdb: 32.2 GB, 32212254720 bytes
64 heads, 32 sectors/track, 30720 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes

Disk /dev/sdb doesn't contain a valid partition table

Disk /dev/sdc: 32.2 GB, 32212254720 bytes
64 heads, 32 sectors/track, 30720 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes

Disk /dev/sdc doesn't contain a valid partition table

Disk /dev/dm-0: 32.2 GB, 32212254720 bytes
255 heads, 63 sectors/track, 3916 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/dm-0 doesn't contain a valid partition table

Another check confirms this:
[root@ps-dev-nfs ~]# blockdev --getsize64 /dev/dm-0
32212254720

[root@ps-dev-nfs ~]# multipath -ll
dev_nfs_fs (36090a028c03879db73a7a4a8bd94a9c6) dm-0 EQLOGIC,100E-00
[size=30G][features=1 queue_if_no_path][hwhandler=0][rw]
\_ round-robin 0 [prio=2][active]
\_ 1:0:0:0 sdb 8:16 [active][ready]
\_ 2:0:0:0 sdc 8:32 [active][ready]

However, when I check disk space usage I still see that device at 15GB:

[root@ps-dev-nfs ~]# df -kh
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 39G 2.6G 34G 8% /
tmpfs 250M 0 250M 0% /dev/shm
ps-home-nfs.plansource.com:/home
50G 41G 6.6G 86% /home
/dev/mapper/dev_nfs_fs
15G 15G 0 100% /mnt/filestore

What step am I missing here?

Can someone please help me ?

Click Here!