We have a MSA30 MI with the 4-port SCSI card in the back. Whilst the dual bus and 4 connectors provides failover in our 2-node cluster, does the I/O card itself not represent a fundamental SPOF?
We took it out to have a look and it is one unit, and therefore if that dies then all communication with the MSA will be lost?
You are correct: the I/O module in the MSA30 MI does represent a SPOF. Redundancy is provided through two buses and four channels, but if the entire card experiences a fault, you will lose all paths to your data. If you are concerned, you may want to keep a spare module on hand (HP Part # 335882-B21).
As you can see, there is no option to add a second module. You might want to consider purchasing a second MSA30 and creating a RAID-1 set between the two through hardware or software (Mirrordisk/UX).
