Fibre and SATA disks are in a separate drawer within an EMC Clarion CX3-20. I have a 2G switch and a 4G switch each server has dual HBAs. I'll be using I/O load ballancing software: PowerPath or MPIO.
As an aside on the I/O balancing: I've used PowerPath in the past but it had serious stability problems on rhel4 when it couldn't queue I/O and drove the load to 500 requiring a hard bounce and e2fsck. I since mounted one device directly (instead of /dev/emcpowerX) forgoing failover and load ballancing in favor of stablity as a tempory fix. EMC says the new powerpath won't have this bug and I'm also looking into changing to multipathd, though I hear it confused LVM (by incremening device numbers). |