On Thu, Aug 23, 2007 at 11:02:28AM -0400, Jeff Blasius wrote: > Hello Jakob, > A couple of things... > 1. ClusterFS has an easy to understand calculation on why raid 6 is > necessary for the amount of disks you're considering. You do need to > plan for multi-disk failure, especially with the rebuild time of 1TB > disks. > http://manual.lustre.org/manual/LustreManual16_HTML/DynamicHTML-10-1.html#wp1037512
As Greg pointed out, if I can live with isolated filesystems (many small RAID sets), there's a lot of problems with very big arrays that won't affect this setup. That said, RAID 6 is probably very interesting to consider anyway. > 2. Avoid tape if you can. At this scale, the administrative time and > costs far outweigh the benefits. Of course if you need to move your > data to a secure vault that's another thing. If you really want to do > tape, some people choose to do disk > disk > tape. This eliminates the > read interrupts on the primary storage and provides some added > redundancy. So far I've been surprised at the number of people who (mainly privately) has told me to stay away from tape - that was unexpected, but interesting nonetheless :) > 3. We do use Nexsan's satabeasts for storage similar to this. Without > commenting on costs, the jackrabbit is technologically superior. > Thanks a lot for the comments! -- / jakob _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
