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No Hassle RAID 5 Implementations?
LambSpam asks: "I had a nightmare week (last week) with two of our servers running Intel's U3-1L RAID controller (RAID 5). Whenever there's a power outage in our building these controllers randomly mark one or more of the drives in the array offline (even with adequate UPS support), which means I have to manually mark them online and/or rebuild. Intel acknowledged the problem, but their solution involves updating the backplane's firmware, the controller firmware (destructive upgrade!), and even the firmware on our IBM drives in the array because they 'draw too much power' in certain conditions. I've only used one other RAID 5 implementation (MegaRAID), and it NEVER had these kinds of problems, whereas if you sneeze too hard around this U3-1L card it will go offline. Is this common with most hardware RAID implementations? What RAID 5 implementations works without hassle? What should I stay away from?"
First, are you sure your UPS is a *TRUE* UPS? Even a lot of the 'high end' UPSes out there are still REALLY switched UPSes. This could very well be your problem.
The other one is something I've heard of (I'm not an electrical expert, but I'll try to explain). Larger (older installations, particularly) sites were wired for three-phase electricity. Over time, they split the phases for normal 110 volt usage. There is a chance where if the PC is connected to power on one phase, but the external unit is connected to power from a different phase, that the differential between the two can cause problems, due to the ground connection between the two through the cable shielding. I know, it sounds like something from the BOFH daily calendar, but it does make sense. Try making sure both pieces of equipment are on the same true UPS, or at least switched UPSes on the same circuit.