multipathing for sglx on rhel 4

[joseph pareti]

I am planning to use 2 dl360-g5's connected to an msa 1500. Each proliant has 2 HBA's cnfigured:

0b:00.0 Fibre Channel: Emulex Corporation Zephyr-X LightPulse Fibre Channel Host Adapter (rev 02)
0b:00.1 Fibre Channel: Emulex Corporation Zephyr-X LightPulse Fibre Channel Host Adapter (rev 02)
13:00.0 Fibre Channel: QLogic Corp. ISP2432-based 4Gb Fibre Channel to PCI Express HBA (rev 02)

The SGLX A.11.18 release notes recommend using the qlogic driver, "Using the QLogic HBA driver for single-path or multipath failover mode on Linux systems", but how to handle the emulex device for the redundant path?

[skt_skt]

Could you specify the RH release and the kernel

[skt_skt]

just noticed the subjetc..So what is the update?

[joseph pareti]

i am using rhel 4 u5
### OS status and version
Linux version 2.6.9-55.ELsmp (brewbuilder@hs20-bc2-4.build.redhat.com) (gcc version 3.4.6 20060404 (Red Hat 3.4.6-3)) #1 SMP Fri Apr 20 16:36:54 EDT 2007

[Serviceguard for Linux]

The document was not update when we supported Emulex. Serviceguard for Linux supports the Multipath functionality delivered by the driver. So using the Emulex multipath functionality is supported.

I believe this is listed in the certification matrix

[joseph pareti]

OK, it's good to know that Emulex is supported, but I would need some "how-to" guide to define multipathing.

I have one Emulex and One Qlogic HBA in each server; the documentantion in "HP StorageWorks Using the QLogic HBA driver for
single-path or multipath failover mode on Linux systems application notes" only covers Qlogic.

[Serviceguard for Linux]

You should post two questions to one of the storage forums.

1) Is it supported to have QLogic and Emulex in the same server with both multipaths enabled.

2) How do you enable multipath on Emulex on Linux.



I am not sure if #1 is supported but I believe someone in that forum will know.

[ralfbosz]

For number 2 I can give you this link from RedHat I found (and used for our SAN multipathing): http://people.redhat.com/nayfield/storage/RHEL4Storage.html

This was used on a system without ServiceGuard (so just a machine having some SAN-disks). For the shared LVM this can be used, but not for the LOCK-lun, that has to be a cciss of sd? device (bummer).

[Serviceguard for Linux]

To be clear, for Serviceguard for Linux, HP does not yet support DeviceMapper.

[joseph pareti]

indeed, it is also my understanding that we need to rely on the HBA's for multipathing.

In addition MSA 1500 should be configured in active/active mode according to the following documentation:

http://essa.corp.hp.com/salesportal/hptf2006/final_presentations/1350_McConnell.ppt (slide 44 and following )

http://h20000.www2.hp.com/bc/docs/support/SupportManual/c00865820/c00865820.pdf