How to get Linux to see expanded partition size on cciss RAID migrated from RAID 1 to RAID 1+0

[campbellmc]

Hi,

I have migrated/expanded a RAID-1 (2 x 72GB) array on a proliant DL360 G5 (SmartArray p400i) to a RAID-10 (4 x 72GB) via hpacucli. The server runs CentOS 5.5 x86_64. Once the expansion was done, the size appears to show correctly in /sys:

cat /sys/block/cciss\!c0d0/size
286611840

I ran 'partprobe /dev/cciss/c0d0' to re-read the device, however fdisk still shows the device size to be 72GB.

I can't find anything in /sys or /proc which would allow me to tell the kernel of the new size, though an HP doc says the cciss driver should do this automatically

"The cciss driver communicated directly with the block layer to inform it of size changes
in the underlying logical disk devices."

(source: http://h20000.www2.hp.com/bc/docs/support/SupportManual/c02677069/c02677069.pdf)

Aside from a reboot, is there anyway I can get the kernel to see the new size of the underlying device?

Regards,

Campbell

[wobbe]

You probably need to extent your partition(s)
What file system are you using?
try www.partedmagic.com

[Goran Koruga]

Hello.

Try:

sfdisk -R

Regards,
Goran

[Alzhy]

Try re-scanning your SCSI bus:

cd /sys/class/scsi_host

for host in host*;do
echo "- - -" >${host}/scan
done

If that fails (as it faied in another posting not too long ago) then reboot. Said technique always works though on my SAN Based RAID disks when I perform online expnsion.

Cheers

[campbellmc]

Hi,

Thanks for the suggestions.

I ended up rebooting the box as I'd run out of time to get it finished. I will do this on a test server sometime though, as I would like to see if I can get it to work.

Re: sfdisk - I saw this and contemplated it but never tried it, on the basis that 'partprobe' never worked. But I had nothing to lose by trying so should have :-)

Re: /sys/class/scsi: I'd seen this suggestion somewhere else to, and not sure why, but there are no hosts in /sys/class/scsi, the directory is empty. Not sure what populates this directory.

I am interested as to why this didn't work, since the new size was reported in /sys. Not sure what block layer or whatever needs to be updated :-/

Cheers,

Campbell