Recognizing new disk space

Question

i have migrated a small LUN to a larger LUN. How do I get my windows host to recognize the extra space. All i see in disk manager is unallocated space. i thought all the space was supposed to show up as i block. I have rebooted the windows host already. any help would be greately appreciated

RRR · Accepted Answer

Silly question: is it a basic disk or a dynamic disk ?
AFAIK expanding dynamic disks this way won't work. It has to do with the location where Windows stores it's information about the disk. Since you rebooted your host already and still have access to the disk, I suppose you have a basic disk.

Use diskpart, select disk, select partition, extend. Something like that; pretty straightforward.

dynamox · Answer

in Disk Management it should look like unallocated space (gray area) right next to the existing partition. Did you use diskpart to expand the drive ?

nandas · Answer

You have to use diskpart utility to expand the partition on Windows as "dynamox" mentioned. Migrating a LUN to a bigger size one will not automatically expand the partition on Windows. You may find diskpart.exe in the resource kit.

Thanks,
Sandip

Hubble1 · Answer

I migrated all the info over during the weekend and did a reboot of the windows host. I could see the unallocated space. I was able to list disk and partition info but I was unable to retrieve the volume info using list volume. I pulled it up this morning and everything listed as it should. i ran the extend command and all worked well. Not really sure what happened.

RRR · Answer

If you do reconfigs on existing LUN's always check whether your OS can handle the changes. Especially any changes with alignment and extending the size are pretty scary stuff

RRR · Answer

Congrats, but not all filesystems can deal with it. Be aware of Windows Dynamic disks. Expansion is ok with basic disks.

riker82 · Answer

I've always done it in production during working time.... For example in Sybase device or Oracle datafile lun, in both enviroment using diskpart and extend command... IT WORKS!

riker82 · Answer

RIGHT!

RRR · Answer

Do you need any more information or are you fine with the provided answers ?
As said "diskpart" (windows) can expand partitions on expanded disks.

If you're fine with the answers, please mark the question answered and mark the answers you think provided you with the best information as "helpful" and "correct".

Regards,
RRR

Hubble1 · Answer

I apologize for the late delay as i have been away from the office. Your answers and advice here have been a graet help and i really appreciate it all. I have awarded points and i hope i did not miss anyone. I apologize if i did.

Thanks

CLARiiON

Recognizing new disk space

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