3510 Config with Expansion Units
Hello,
I'm reconfiguring a 3510 with 2 controllers and 1 expansion unit. It will be the storage portion of a Veritas cluster, with 4 hosts directly attached and redundant paths managed by DMP.
The best practices guide states:
"For best performance and RAS, create logical drives across expansion units."
I interpret that to mean, create the logical disks with a mixture of physical disks from both units. This definitely makes sense when you start getting into huge logical disks and want to maximize usage of the 2 Gb fiber channel bandwidth. I understand the performance part of the sentance in the documentation.
But I'm having trouble with the availability part of their statement. If I create logical disks spanning multiple expansion units, and for whatever reason I lose an entire expansion unit, my entire logical drive is then unavailble (unless I am missing something here).
I know this is a remote possibility since nearly everything in the 3510 is redundant, but I wondered if anyone had any thoughts. Short of mirroring an entire logical disk using software, which seems a tad extreme, does anyone have thought on this type of thing? Would you do it differently, trying to keep a single logical disk within a single enclosure?
Thanks for reading and any input.
