How to set up a hot spare disk with MSA 30 ?

[TonyJK1]

We are using MSA 30 with 11 HD. Someone has set up the disk array so that 5 HD is assigned for Netware and 5 for a Windows 2003 Server. The remaining one is for just for spare.

However, we would like to set up the spare HD as a hot spare disk for the Windows 2003 Server.

I would like to know seek your advice on
1) Setup Procedure
a) Connect the HD to Windows 2003 Server
b) From ACU, there will be one extra HD showing status of Online

2) When one of the HD fails
a) When one of the HD fails, will the Array Controller automtically pick up the online HD and rebuild ?
b) When we replace the HD, is it necessary for us to do anything to the online (backup) HD ?

Thanks

[Rob Leadbeater]

Hi,

Can you confirm exactly how you have things configured please... The MSA30 is just a disk shelf, it doesn't have any controllers.

As you've got it connected to two servers it is likely to be a dual bus model. So you've probably got a SmartArray controller in each of your two servers. The exact setup procedure will depend on the type of controller, however it should just be the case of designating the drive as being a hot spare.


Hope this helps,

Regards,

Rob

[TonyJK1]

Dear Rob,

You are right. The MSA 30 is a dual bus model with no Array Controller. From ACU, I find that the Array Controller used on the Windows 2003 Server is "Smart Array 642 Controller".

I would like to ask
1) Does it mean that a "Daul Bus Model" can support more than 1 server (What is the maximum number of servers that can connect to it ?)
2) Could it be possible to give me some advice on those questions mentioned in my original question ? (I am sorry that I am new to storage and this company).

Thanks

[Sandy Chen]

Hi,

Yes, "Dual Bus Model" can support more than 1 server, but each server only can handle half of full capacity (7 disk each)

About the failing disk, if there is a spare disk, the if a disk failed, it will automatically use the spare disk.

About backup, even there is no HDD failed, you should have a daily backup, either online of offline. So that if there is incident like a failed disk, you already have a daily backup.

Regards,
Sandy

[TonyJK1]

Dear Sandy,

In other words, we can only use 2 Servers with the MSA 30 Disk Shelf ?

When the spare HD is connected, is it necessary for me to do any tweaking on the Array Controller on the Windows 2003 Server ?

Thanks

[Rob Leadbeater]

Hi,

Yes you can only use two servers with a MSA30 Dual Bus shelf.

If you go into the ACU (Array Configuration Utility) on the Windows 2003 box, you should see the option to designate the drive as a hot spare. Note that the drive must be in the same half of the shelf as the other drives on the 2003 box to be seen by that controller.

Cheers,

Rob

[TonyJK1]

Dear Rob,

In this way, it is unlike the ACU user guide says "Any spare can be shared by several arrays" although it is right that "An array can have several spares".

OR I have misunderstood the statement as it mentions a SAN instead of DAS ?

Regards

[kris rombauts · Accepted solution]

Tony,

to clear up the confusion here, since you are using two servers to connect to the MSA30, as already mentioned, one server will only see half of the MSA30 (so 7 drives, not all 14 slots).

Server A will see the left half of the MSA30 and server B will see only the right half.

This means that in order to have a hotspare disk protection for each array, you need to add one extra disk to the half of the MSA30 which has only 5 drives right now and configure it as a hotspare via that server's ACU utility.

You cannot share a spare disk between 2 servers since each server only sees the half of the MSA30 (either left or right half).

If you only want to have the hotspare on your W2K3 server and not your Netware server, then remove the hotspare from the Netware server (via the ACU utility) and put it in a free disk slot on the half of the MSA30 that can be seen by the Windows server.

The manual says that a hotspare can be dedicated to one array or global (shared between arrays) , this is true but only within the same server (smartarray controller) and not accross servers or controllers and for sure in this case since only one server can really see the hotspare disk due to its physicall location.

So just think about the MSA30 as being 2 separated 7 disk shelves in your case.

Answers to your questions:
--------------------------

The setup procedure for a hotspare is via "spare management" function in the ACU
utility. See the SmartArray user manual on hp.com

When a disk fails, the hotspare will automatically start to rebuild the data to make the array redundant again asap. When you then replace the bad disk later , the rebuild will be done again from the hotspare onto the new disk and the hotspare disk will become idle again for eventual next disk failures.

There is nothing you need to do at the backup server level or backup jobs, the disk array works independent of the backup server and a disk failure is not seen by the backup server.


HTH

Kris

[Sandy Chen]

Hi,

"Any spare can be shared by several arrays" I think this one goes for SAN, not for DAS.

Regards,
Sandy

[TonyJK1]

Dear all,

Thanks for your advice

Regards,