Raid Support

[Sreedhar.T.P]

I have a ML350 G4P server which has Smart Array 642/64 raid dual channel raid controller and an onboard scsi (single channel) controller. The system has two 36GB scsi harddisks and four 72GB scsi harddisks.(All Hot Swap)

The customer wants to do Raid 1 (mirroring) for operating system with the two 36GB scsi and Raid 5 for the database with the four 72 Gb's.

Is it possible to do hardware raid (1&5) both with the same controller. If any suggustions or solutions please reply

[Ken Henault]

There's a few ways to do this.

If you only have one server to configure this way, just use the ROM based setup utility (RBSU)by pressing F8 during post, and configure the array manually. Then create a copy of the scripted install job in RDP,Delete the deploy Array Configuration and it's reboot from your custom job.

If you want to deploy multiple servers with this configuration, use RBSU to manually configure the array as above. Then use the "Read ProLiant ML/DL/BL Array Configuration" in the server deployment toolbox to capture this array configuration. You'll need to modify your scripted install job to use this array config file.

[Gordon Leonard]

Consider this - The bottleneck in storage is the drive. To maximize through-put you add spindles (hard-drives).

On the Smart controllers you can create virtual RAID sets - ONLY HP Smart RAID controllers can do this no other vendor can do this!!!



Ground rules:

1. Stop thinking of RAID sets as drives in a set. I mean it, stop it right now.
2. To do this you need to use an EVEN number of drives (don't count the hot spare).
3. The drives must be the same size.

For example.

I need 8GB of RAID 1 and 96GB of RAID 5.

I would use four drives (see rule #2).

Place all the drives in an array (array 'A').
This will create the total raw storage of (4x36) 144GB.

Create a logical drive that's 8GB in size RAID 1 (this will use 16GB of RAW space thus 144-16=128).
Create a logical drive that's 96GB in size RAID 5 (this will use 128MB of RAW space thus 128MB RAW / 4 Drives = 32MB, The overhead for RAID 5 is the space of one drive so 3x32=96).

Doing this has just maximized the spindle count for both RAID sets.

Something to think about.

[Sreedhar.T.P]

Sir,


It is not possible to do as you has given in the example.

The customer does not want any other solution other than his interests.

I would like to know whether it is possible to create multiple raid sets ie Raid 1 and Raid 5 both on the same controller. The raid controller is dual channel and the scsi controller is single channel.

[Steven Clementi]

Sreedhar:

As long as the Array Controller can see all 6 drives, then yes, you can create your configuration.

You would create 2 different arrays. Array A would be the 2 36GB drives. In this array you create 1 logical drive with RAID1 configuration.

Array B would be the 4 72GB drives. In this array you create 1 logical drive (or more) with RAID5 configuration.



Steven

[Sreedhar.T.P]

Sir

Thank you for the reply.

If so can i make the raid1 array bootable(for operating system) and raid5 array for database.

Please explain how to select the bootable array. Can i select the bootable array manualy.

[Steven Clementi]

Normally, the first logical unit you define in the first array that you create holds your OS/System partition.

Assuming you are installing Windows or Linux or even Netware, you should be able to select which drive(s) you want to install your OS to during the installation process.


I would create the first array with the 36GB drives and create a logical drive of 36GB RAID1. Install your OS, then aftwerwards, use ACU to create the second array and second logical drive.



Steven

[Sreedhar.T.P]

I have found the solution