RAID 5 disk migration to MSA500

[John Litwin]

Greetings. I have a client who would like to move a RAID 5 array from an MSA30 DAS to an MSA500G2 DAS. Will simply moving the drives over to the MSA500 work, or do we need to create a new RAID 5 volume on new disks and migrate the data? A cursory search seems to indicate to me that data migration is the only option, but it'd be helpful if someone could confirm this. I'd really rather move the disks if the MSA500 can recognize the existing array. Thanks.

[Albatross]

Hi John,

I've performed this in the past, with drives from the Smart Array 642 to the MSA500, loosely did this:

0. Backup and verify all data, rollback plan
1. Shut down server where the drives reside
2. Record the positions in the bays/drives
3. Move the whole group from the server to the disk shelf, one RAID group at a time
4. Power on the MSA500, let the controller detect and enable the array, may need input in the controller's display.
5. Present drives, verify data

Take a look at the MSA500 data sheet

http://h18004.www1.hp.com/products/quickspecs/11050_div/11050_div.HTML

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In addition to convertibility to the SAN, the Modular Smart Array 500 allows the seamless migration of stored data in ProLiant servers protected by Smart Array PCI controllers to a Modular Smart Array 500 system. Data that is currently stored on 1" Universal disk drives using HP Smart Array controllers, as well as data on an RA4100 can easily be migrated to the Modular Smart Array 500. Simply remove the drives from the older systems and insert them into the Modular Smart Array 500. Existing data and configuration will remain intact. In addition, the RAID set and data will be preserved allowing migration to be completed in minutes, not hours.
-----------------------------------

Hope it helps,

Albatross

[John Litwin]

Thanks Albatross. I recall now that I did, in fact, read this a while ago. I've tried transferring the disks as you've outlined. Unfortunately, it didn't work. The MSA500 reports the error 'Invalid Volume Addition'. The manual says to 'remove the invalid volume', but there is only one volume comprised of the entire disk set.

However, as I'm writing this, something has just dawned on me that you might be able to confirm: I'm a little unclear as to whether the array configuration is stored in the controller's nvram or on the disks themselves or both. Does the MSA500 have to be connected to the same server with the controller that currently has the configuration information? My initial attempt was with another server because I was concerned about keeping a fallback position in case it didn't work. Perhaps this is the very reason it failed.

[Albatross]

John,

If I remember correctly, the metadata is stored in the drives, so the whole group may be transported between servers, in the very same order it was installed in the original controller.

As a suggestion, I'd do a controller firmware upgrade in both disk controllers (SA and MSA) *before* moving the drives to the MSA in order to update or refresh the array metadata.

The fact that both controllers are in the same system should not be a problem, but you might remove the SA before trying to boot and recognize the volume in the MSA (unless the the SA is working as the "HBA" communicating with the MSA500 OR the SA is running another volumes in the server)

Hope it was somewhat clear,

Cheers,

[John Litwin]

Al,
Clear enough, thanks. The MSA f/w is already up to date. I've updated the f/w for the SA5i that apparently does act as a HBA as near as I can tell. My next window of opportunity for the migration isn't for another 10 days or so. I'll post a result here then.
John

[Mike_Cool]

Hi did you get the solution on what happened? I have a similar situation. I have added 3 drives from another DL380 G4 server to existing DL80 G4 server. I can see the disks in controller but it doesnt detect the RAID settings. Do we need to do something for them to detect the configuration from the disk.

Note: Three drives are inserted in same order as like old server.

[John Litwin]

Hi Mike. I have no joy for you. Other decisions were made and the client opted to create a whole new, larger array. Consequently, they didn't need to migrate the old disks and I never did find out what was preventing them from being accepted by the MSA500's controller.

[gregersenj]

> Mike.
If you move drives from 1 Smart Array controller to another it should work strait away. Even if you get the positions mixed up.

A few basics, you need to beware of:

when you're messing with disk's you're always taking a risk.
A good backup, recovry and fall back plan, is a must.

Smart Arry controllers are data compatible, but not driver comaptible, between generations.
So if you are moving from one generation to another, you need to install the driver first.

This is an offline operation = Power down both machines.

All information aboute, the RAID setup, status, disk positions, is stored in the ris area on the disks as metadata.
All information is copied to all disks.
And it is time stamped.

If you want to put an array from machine 1 in machine 2, along with excisting array you might get a conflict.

if you use ADG/RAID 6, do ensure that the new controller support it.

Also ensure that the new controller got same FW level or newer.

If you get the posistions mixed up, the SA will prompt you to confirm (Press F1)

BR
/jag

[Mike_Cool]

Thanks for the reply. I however tried and updated the firwmare version same as my old DL380 G4 server and still same issue. It sees the drives but doesnt detect the RAID configuration and logical partition.

I somehow need to get the data from this raid partition. Please let me know if there is any other way to recover my data.

Thanks

[John Litwin]

Mike, in my situation, we are going to copy the old data over to the new array. This requires having both the old and new servers/arrays running, of course, but isn't this possible for you?

[Mike_Cool]

No Thats not possible because the old server is allready dead and its working anymore

[John Litwin]

That's unfortunate. You've probably considered them, but here's what I see as options:

1) Get the old server running. There's all dead and then there's mostly dead. If possible, replace whatever's hooped even if it's with used parts.

2) Go through 'HP StorageWorks Modular Smart Array 500 System User Guide' page 4-7. This is the only description I've found from HP of the disk migration process for the MSA500. I imagine that it can be applied to your situation with the new server. Apparently, the migration should be easy. However, as we both know, this is not always the case. If your hardware problem was the RAID controller itself, I suppose the possibility exists that the RAID metadata on the disks is corrupted.

3) If all else fails and your data is worth it, take the disks to a data recovery service and have them try to retrieve what they can.

[gregersenj]

It seem to be a challange.

I wrote how things work, when it work as expected.

Normally. Lets imagine you suffer from a defective Smart Array controller.
You get a new identical controller.
You install the new controller and power on the server. And it will find the RAID configuration from the drives, and will boot and run without any problems what so ever.

In you case, something isn't working as it expected.

If I were in your situation, here's what I would do.
Get the server in known good state.

To do that:
remove the disk's that you want to use/keep.
put them away, to keep them safe.
Then use another disk(s) for trouble shooting the server.

Once you got the server in a know good state, then install the disk's and try again.

But thinking over you're problem:
You tell us, that the server see the disks, but it don't see the RAID.
If that is true, then the META data seem to be deletet.
Are you sure, that is a correct observation?
If you hit F8, when prompted by the RAID controller, is there no logical drives?
Only physical drives?

Have you put the disks in the server along with an existing Array, so that you got 2 times Array A, on the same RAID controller?

Have you deletet the cmos, from the RBSU (BIOS setup)? If so you might accidential deletet the RAID.

Note:
I did see a strage problem, due to a bad disk, aboute a month ago, in that case it was SAS disks though, RAID 1.
But when both disks was installed, it would not boot etc.
If i put in 1 disk only, no matter wich, it bootet fine.
It was caursed by a bad disk.

But anyway, do try to get the server in a known good state.

BR
/jag

[Mike_Cool]

I Jag,

Thanks for the reply. I however tried the option with other disks and it detect the RAID from those disks but when i try on the disk which i need i get error in Array Diagnostic report "RIS Within the Disks do not match". I have tried it in like 3 servers and all 3 servers i get same error message.

I have cleared teh old RAID configuration from server before i inserted this disk but still same issue.

There should be something from HP where we have the option to force the RAID configuration and logical partition from Disk and also to resolve the RIS mismatch. I have searched most of the blogs and there has never been a solution for this problem.

MOst of the cases we need to rebuild the RAID from scratch and restore data from backup. This totally spoils the concept of data redundancy on RAID.

[gregersenj]

"RIS Within the Disks do not match" - Thats bad.

I have no knowledge of a tool, that can save that.


RAID is a good security, but it's not 100% safety.
You still must take backup.

You do have a risk, of multible disk failure, that can take down you RAID.
Other failure can corrupt you RAID.

The most common reason for dataloss, is user errors and virus.

Then there's theft and fire.

I do understand your frustration, but it do happen.

BR
/jag