Adding drive to RAID5 array

[Homerboy]

Currently have Dell 2950 server with a perc controller card running Win2k3
We have 4x146GB SCSI in it and I need to add another HDD to expand the space.

My question is can I do this on the fly? Can I just plug in the HDD while its running, the card AND windows will pick up the new HDD and add it to the array, or do I need to shut down, insert new tray fire it up, define in the RAID bios then adjust in Windows too?

I'd imagine that IF it did it on the fly performance would suffer while the array was being rebuilt.

 

[Homerboy]

n/m
God bless Dell's support
so good.

 

[RebateMonger]

Originally posted by: Homerboy
n/m
God bless Dell's support
so good.

So, what did Dell say?

 

[Homerboy]

Originally posted by: RebateMonger

Originally posted by: Homerboy
n/m
God bless Dell's support
so good.

So, what did Dell say?

2 step process.

#1 (using Dells Admin software) add the Disk to the array
#2 using diskpart.exe assign the new unallocated space
#3 hold your head high

As a tad more info the current array (1 logical disk) is split into 2 partitions (well 3 if you count Dell's little chunk.

 

[Homerboy]

*these steps did not work
emailing support back

 

[Nothinman]

If the hardware part of it works, i.e. you can hotplug the drive and add it to the array then you're just left with figuring out how to get Windows to resize the volume. And I don't believe Win2K3 can resize volumes live so you're looking at having to at least dismount the volume.

 

[Homerboy]

Originally posted by: Homerboy
*these steps did not work
emailing support back

I take that back... it is working. Just not as Support/I envisioned. The array has to be rebuilt 100% before you can use diskpart on it. So we're chugging along at about 1% every 5mins ....

 

[Homerboy]

Originally posted by: Nothinman
If the hardware part of it works, i.e. you can hotplug the drive and add it to the array then you're just left with figuring out how to get Windows to resize the volume. And I don't believe Win2K3 can resize volumes live so you're looking at having to at least dismount the volume.

http://support.microsoft.com/kb/325590
seems diskpart.exe does allow it.

 

[RebateMonger]

I don't believe you can change SYSTEM PARTITION sizes with Microsoft tools. But you can change other partitions.

Hopefully you have good backups of all your stuff.

 

[Nothinman]

http://support.microsoft.com/kb/325590
seems diskpart.exe does allow it.

The KB article doesn't really say either way, I might have to give it a try in a VM just to see.

 

[Homerboy]

Originally posted by: RebateMonger
I don't believe you can change SYSTEM PARTITION sizes with Microsoft tools. But you can change other partitions.

Hopefully you have good backups of all your stuff.

correct
this is a non OS partition.

REBUILDING all day.... 82%! with 50% of my staff able to work
Dell screwed me!

 

[Nothinman]

REBUILDING all day.... 82%! with 50% of my staff able to work

Yea, it's gotta restripe the data so that's going to take a while.

Dell screwed me!

Big surprise there...

 

[Fullmetal Chocobo]

Originally posted by: Homerboy

Originally posted by: RebateMonger
I don't believe you can change SYSTEM PARTITION sizes with Microsoft tools. But you can change other partitions.

Hopefully you have good backups of all your stuff.

correct
this is a non OS partition.

REBUILDING all day.... 82%! with 50% of my staff able to work
Dell screwed me!

Dell told you the correct steps. They just didn't advise how long it would take. Building RAID 5 arrays and modifying them (capacity expansion, stripe size reassignment, etc) always takes time--the more space you have, the more time. I'm surprised you did the operation when your staff was there working.

 

[Homerboy]

Originally posted by: Fullmetal Chocobo

Originally posted by: Homerboy

Originally posted by: RebateMonger
I don't believe you can change SYSTEM PARTITION sizes with Microsoft tools. But you can change other partitions.

Hopefully you have good backups of all your stuff.

correct
this is a non OS partition.

REBUILDING all day.... 82%! with 50% of my staff able to work
Dell screwed me!

Dell told you the correct steps. They just didn't advise how long it would take. Building RAID 5 arrays and modifying them (capacity expansion, stripe size reassignment, etc) always takes time--the more space you have, the more time. I'm surprised you did the operation when your staff was there working.

Actually they did tell me the steps. THEY didn't think the reconstruction would take nearly that long (in fact IIRC the words "a few seconds" were mentioned). Even so after it did take a long time they were even amazed and bewildered that it impacted the staff as much as it did even with the reconstruction rate set as low as it would go.

The only explanation they/we could come up with is that the storage iteself contained a gazillion small .tiff files (scans) that likley just thrashed the hell out of the drives as it rebuilt.

 

[Lorne]

I agree that it should of only taken a few min at most, Im sure fragmentaion may played a part as well, I had rebuild one failing badly, 3 300 gig and 2 went out, being hotswappers I replaced the 2 and it was only about 45 min at most to have it done but there was no other access from outside as the system poor all resorces to finishing the raid, I then spent 15 min replacing the first drive kind asured it would go soon also.

I think yours is taking longer also to the fact your adding and contingent as to just replacing what it should of already had, Having to recalculate all checksums and placement.

 

[Nothinman]

The only explanation they/we could come up with is that the storage iteself contained a gazillion small .tiff files (scans) that likley just thrashed the hell out of the drives as it rebuilt.

That shouldn't matter at all, from the array's perspective the files on there are just random bits. It doesn't understand the filesystem at all so it has to rearrange all of the data even if it's empty space.

 

[Peter]

Exactly ... reading and writing back hundreds of gigabytes of data is going to take a LONG while - particularly when constantly interrupted by users (gah! users!).

Be patient.