I'm not a storage guy. I know how to spell SAN and a few basics beyond that, but not much farther.
Are std disk counters reliable in measuring against SAN storage? We have 2 MS SQL (2005) servers both attached to the same SAN that started experiencing problems yesterday. We're not in control of the hardware so I don't have much information on how the storage is configured, other than what I see down to the LUN via Veritas Enterprise Admin (ie- just basic volume configuration). I don't have any access to the tools to monitor throughput on the controllers or switches.
In lieu of that I was running perfmon counters (% disk time for physical and logical, disk queue length for both physical and logical). The numbers for % disk time for Physical Disk seem just whack - up to 32000% (yes, 32K).
Is that right, or am I correct in thinking that something is aggregating up from below the LUN level to make that metric and this counter is not something that I should use against SAN storage?
Should add that we've recently discovered that one of the 32 cache modules is having issues and was taken out of the mix. I know it's a Hitachi, but I don't know any specifics as to model.
Hitachi just finished swapping out the faulty memory module and reinitializing the fiber port card, now things appear to be back to normal. Thanks for the info guys!