The Smart array cannot detect the 3rd disk (disk2) in the rx2620 internal disks bay

[Yaboto]

Hi,

I have installed three disks of 300GB each into an RX2620 internal disks bay. The smart array could detect only two disks (disk0&disk1) then I could create a logical drive with only those two disks. The 3rd disk could not be detected by the smart array, but could only be detected only at the HP UNIX OS level.
Why can't the smart array detect the 3rd disk so that I can create a raid5 logical drive with the 3internal disks ?
What is the problem ?

Please help

Regards,
Berag

[kris rombauts · Accepted solution]

Berag,

The disk backplane consists of two parts.

Check the manual at http://bizsupport1.austin.hp.com/bc/docs/support/SupportManual/c00752367/c00752367.pdf chapter 8 page 79 and you will see that you likely have the second part of the disk backplane still connected to the internal SCSI controller and not to the SmartArray controller.

So at bootup you will see one logical drive from the SmartArray controller and one standalone hard disk connected to the SCSI onboard controller.

So change cabling and all should be fine to create a raid5 array.

HTH

Kris

[Kranti Mahmud]

Hi Berag,

rx26XX model server has a Smart Array Ultra160 SCSI RAID card which supports only 3 disks, of them you can use 2 disks for RAID-1 & 1 for internal drives.

It is not a problem, but it is feature of rx2620 as it is very low end server of rx.
For more clarification, check the following link:

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&taskId=120&prodSeriesId=447331&prodTypeId=15351&prodSeriesId=447331&objectID=c00272435

Rgds-Kranti

[kris rombauts]

The previous post by Kranti needs some corrections, not sure where the information is based upon....


- first of all, the SmartArray is a optional controller for the RX26XX, if not installed , you have the default two channel SCSI U320 (not U160!) controller which cannot do hardware raid.


- secondly, the disk backplane is split in 2 parts as i explained before (pls read the manual !) and SCSI id = 0 and 1 are separated from SCSI id=2, so you need to use two channels and 2 SCSI cables if you want to use one array with 3 disks to make a RAID5 i.e.

The issue Berag has is likely that only one SCSI cable is connected to the SmartArray and the other cable is still on the embedded U320 SCSI controller, so that cable needs to be moved onto the Smartarray second channel. The boot process will show you if that third disk is visible by the U320 build in controller or not.


There is NO limitation in this server to create a 3 disk array at the hardware level, both smartarray channels can be used for the 3 internal disks, the only limitation could be at the OS level and the support for certain configurations.


HTH

Kris

[Yaboto]

Thanks very much, Kris

Best Regards,
Berag