hpcuacli - removing a drive from a raid set - smart array P400

[Jonathan McDougall]

Hello,

I erroneously added a spare physical drive to an array, and had to wait a day for the array to grow over the new drive. What I really wanted to do of course was create a new logicaldrive and present a 2nd LUN to the host...)

I'd like to remove this physical drive, and return it to the "unassigned" pool, but I can't seem to do this. Does anyone know how this may be accomplished ?

We didn't grow the logicaldrive over the newly expanded RAID set, so the LUN seen by the host is unchanged.

I have appended the config output below. Any assistance would be appreciated - this is a dev/stage system, but I'd rather not blat the entire array if I can help it :-)

Thanks in advance,

Jon.


=> ctrl all show config

Smart Array P400 in Slot 1 (sn: P61620G9VVO7W7)

array A (SAS, Unused Space: 0 MB)

logicaldrive 1 (410.1 GB, RAID 5, OK)

physicaldrive 2I:1:1 (port 2I:box 1:bay 1, SAS, 146 GB, OK)
physicaldrive 2I:1:2 (port 2I:box 1:bay 2, SAS, 146 GB, OK)
physicaldrive 2I:1:3 (port 2I:box 1:bay 3, SAS, 146 GB, OK)
physicaldrive 2I:1:4 (port 2I:box 1:bay 4, SAS, 146 GB, OK)

unassigned

physicaldrive 1I:1:5 (port 1I:box 1:bay 5, SAS, 146 GB, OK)
physicaldrive 1I:1:6 (port 1I:box 1:bay 6, SAS, 146 GB, OK)



=> controller slot=1 array A add drives=1I:1:5



=> ctrl all show config

Smart Array P400 in Slot 1 (sn: P61620G9VVO7W7)

array A (SAS, Unused Space: 174979 MB)

logicaldrive 1 (410.1 GB, RAID 5, Expanding 36.0% complete) <<--

physicaldrive 1I:1:5 (port 1I:box 1:bay 5, SAS, 146 GB, OK)
physicaldrive 2I:1:1 (port 2I:box 1:bay 1, SAS, 146 GB, OK)
physicaldrive 2I:1:2 (port 2I:box 1:bay 2, SAS, 146 GB, OK)
physicaldrive 2I:1:3 (port 2I:box 1:bay 3, SAS, 146 GB, OK)
physicaldrive 2I:1:4 (port 2I:box 1:bay 4, SAS, 146 GB, OK)

unassigned

physicaldrive 1I:1:6 (port 1I:box 1:bay 6, SAS, 146 GB, OK)


(now would like to remove drive 1i:1:5 from the ungrown logical drive in array A. The "remove drives" function does not work:


=> ctrl slot=1 array a remove drives=1I:1:5

Command Line Entered:
controller slot=1 array A remove drives=1i:1:5

Error: "drives" See help for usage.


=> help remove

remove [spares=[#:]#:#,[#:]#:#,[#:]#:#-[#:]#:#],...|all]
The remove command allows you to remove one or more spares from a specified
array. The target can be any valid array.


Can you really only remove a spare drive ? The "delete" command seems to only apply to a logicaldrive, not a physical drive, and hence appears inapplicable ?

[TTr · Accepted solution]

You can not remove a physical drive from the array. This capability is not available neither on the SA raid cards nor on some large storage array systems.

> We didn't grow the logicaldrive over the newly expanded RAID set, so the LUN seen by the host is unchanged.

That's not true. You not only expanded the array but you expanded the logical drive as well. The new logical drive is probably about 520 - 550GB big.

On the OS side you can grow the existing partition or create a new one.

What is the OS?

If you absolutely wanted a new logical drive, there only way to go back to it is to backup your data, destroy and recreate the array/logical volume and restore your data.

[Jonathan McDougall]

Hello TTr, and thank you for the reply.

I'm confused when you say we expanded the logicaldrive, as this is not reflected in the hpacucli output:

=> ctrl all show config

Smart Array P400 in Slot 1 (sn: P61620G9VVO7W7)

array A (SAS, Unused Space: 174979 MB)

logicaldrive 1 (410.1 GB, RAID 5, OK)

physicaldrive 1I:1:5 (port 1I:box 1:bay 5, SAS, 146 GB, OK)
physicaldrive 2I:1:1 (port 2I:box 1:bay 1, SAS, 146 GB, OK)
physicaldrive 2I:1:2 (port 2I:box 1:bay 2, SAS, 146 GB, OK)
physicaldrive 2I:1:3 (port 2I:box 1:bay 3, SAS, 146 GB, OK)
physicaldrive 2I:1:4 (port 2I:box 1:bay 4, SAS, 146 GB, OK)

unassigned

physicaldrive 1I:1:6 (port 1I:box 1:bay 6, SAS, 146 GB, OK)


I can see that "Array A" now has unused space ~175Gb, but the logicaldrive still shows as 410Gb.

To help my understanding, could you tell me whether the logicaldrive is the LUN that the host sees ? i.e. is the logicaldrive generated *by the array* and presented to the host as a LUN or device, in the same way many storage products allow you to make lvols and present them as luns ?

Or is hpacucli instead reading the lvol config from the host, and displaying that, i.e. simply saying "you've got a 410Gb Linux LVOL on this array" ?

Or do we have an inconsistency somwhere ?

The host is running Suse Linux Enterprise Server 10, patchlevel 1.

Fortunately, we ran three sets of backups yesterday (netbackup, oracle rman, and TSM).

It would not be the end of the world to grow the lvol or scrub the system entirely, but I don't want to make any more changes until I have grasped what is going on...!

Thank you again for your reply.

Jon.

[TTr]

OK, I was misled by

> logicaldrive 1 (410.1 GB, RAID 5, Expanding 36.0% complete) <<--

If you see the unused space in array A, you can create a new logical volume for your OS and it will be seen as a new disk.

Yes the SA arrays are very similar to the large array systems (raid arrays, LUNs etc) and the acucli interfaces directly with the raid controller as the management tool of the raid card.

[Jonathan McDougall]

Ah, I see - I can add a new logicaldrive using the empty space within array A...

Thanks again for your help, all is not lost with this scenario. I can add the 2nd spare drive, and then create a new logicaldrive in the array controller, get the host to recognise the new lun, and add the lun to any existing LVM's on the host/OS side etc...

Many thanks !

Jon.