Fibre channel support for multiple HP servers

[Greg Schneider_1]

Is MC/Service Gaurd required when connecting multiple
HP servers (HP/UX 11.0) to a single arbitrated loop? We have a RAID array with
multiple targets/luns that we wish to mount to several HP systems and we have
gotten some conflicting information about whether or not HP requires service
guard to prevent inadvertant data corruption. What is HP's official stance on
this? If service gaurd is not required, what are the maximum numbers of hosts
and or host adapters that can exist on a loop?

Thank you.

[Melvyn Burnard_1]

The question that needs asking here is which RAID array are you using?
If it is something like and EMC or XP256, thene these units can be configured
to present specific LUN's on specific ports, thus preventing activation on
multiple nodes.
And yes, you can use FC-AL for multiple HP systems without MC/ServiceGuard.

If you are looking at having multiple nodes in the loop see the SAME
disc/LUN's/VG's, then the possibility of multiple nodes activating the same VG
at eth same time does exist, and I would not suggest you do this, without
MC/ServiceGuard.

To my knowledge, there is a maximum of 4 host nodes supported in the same
FC-AL, but you may want to contact your Sales person to have the configuration
verified.