itanium hardware mirroring

[hpuxrox]

Someone told me that the new itaniums have hardware mirroring and do no require lvm. Come someone direct me on how to check if I have such a system?

[Tim Nelson]

If the system has SAS controllers you can HW mirror from the controller.

Look at the SAS admin guide for instructions.

[Sameer_Nirmal · Accepted solution]

In case of new generation of Integrity systems, there are SAS HBAs and SAS Smart arrays HBAs with specific RAID levels are being offered and their use is depends on the OS platform to be used on them. You can see what RAID controller installed on the server when you power on the server and system f/w detects it.

Take a look at the specs of then new servers.
http://h20341.www2.hp.com/integrity/cache/331424-0-0-225-121.html

http://h71028.www7.hp.com/ERC/downloads/4AA0-6159ENW.pdf

To configure the Integrated Mirror is you use EFI utilities as mentioned at
http://docs.hp.com/en/AB464-9001B/ch09s02.html#babhihch

[hpuxrox]

So how would I check if a system has SAS?

ioscan -fnkd sasd

Will that tell me?

[Tim Nelson]

An rx6600 with SAS shows the below.
0/4/1/0 escsi_ctlr HP PCI/PCI-X SAS MPT Adapter
0/4/1/0.0.0 ext_bus SAS Device Interface
0/4/1/0.0.0.0 target
0/4/1/0.0.0.0.0 disk HP IR Volume

[Sameer_Nirmal]

Yes, that's correct command. It will give you something like this.

# ioscan -fnkd sasd
Class I H/W Path Driver S/W State H/W Type Description
====================================================================
escsi_ctlr 0 0/4/1/0 sasd CLAIMED INTERFACE HP PCI/PCI-X SAS MPT Adapter
/dev/sasd0

You can manage SAS storage using "sasmgr" utility as mentioned at
http://docs.hp.com/en/J6369-90045/ch04s02.html

[rick jones]

ioscan is what you would run on HP-UX. on linux you would run lspci.

or, at boot time, if there is a SmartArray (btw, some of the older Integrity servers supported some of the SCSI SmartArrays...) there will be the familiar "Press F8 to configure the array" (paraphrase) message on the console.

whether or not the presence of HW RAID removes the need/desire to use LVM (presumably LVM mirroring I guess) may be one of those "it depends" questions.

also, on the new zx2-based systems, even if there is not a SmartArray, the "embedded SAS controller" (LSI1080 IIRC) can be configured to do HW RAID1. i do not have the specifics handy, but suspect they should be on the per-system docs on docs.hp.com