I would argue that the situation you describe is a result of that particular RAID adapter or that particular make and model is just inappropriate (no offense)
I have certainly seen lots of RAID arrays where multiple drives die at approx the same time, but I find that usually: - multiple drives die at the same time from the same production batch, and my vendor replaces those drives with no questions asked - the drives that died exceeded their production lifetime at approx the same time I'm not sure how a software RAID solution would work around that. It is clear that most of the folks in the list favor software raid, but I have worked with both hardware and software RAID and with different OS and hardware vendors. RAID setups are no different than any other component should be spec'd carefully for their intended target, including the disks. I do favor hardware RAID, myself. I have never had any unexplained data corruption or unresolved performance or recovery issues on my watch. I tend to favor hardware RAID due to the fact I can rely on a level of conformity across an install base (if needed), more flexible admin tools, better support (I specifically choose adapters from trusted vendors) and lower admin overhead. I could certainly choose a cheaper hardware RAID adapter which would result in some of the problem I am trying to avoid... that is where doing the research comes in. I am one of those guys who like to move as many operations closer to the hardware layer as possible.... but it doest cost. Having said that, I am also running software RAID in a medium scale environment now (Redhat Linux and FreeBSD) and it works just fine (along side our hardware RAID systems). I also observe that many vendors will fully populate a RAID-5 array and create no hot-spare (DELL) or only one hot-spare. I usually create two hot-spares in order to give myself the wiggle room to run a medium-large datacenter with a small staff. No need to rush in if a single disk craps out. That would also avoid any kind of "rebuild storm." The data component is so important that I have never had a problem recommending a cluster with such a configuration. Just my two cents. -geoff -------------------------------------- Let me offer up a somewhat concrete example of a problem with hardware raid. A local group around here kept some Very Important Data on a hardware raid array. Due to several factors, a backup was not made of certain data. The device lost a drive and started an automagic rebuild on one of the hot spares. The sudden beating that the other drives took (because of the rebuild) caused a second hard drive to fail (always a concern with RAID5). _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
