> > > I've been assuming that RAID is generally a good idea (disks fail quite > often, and it's cheaper to hotswap a drive than to rebuild an entire box). >
Hadoop data nodes are often configured without RAID (i.e., "JBOD" = Just a Bunch of Disks)--HDFS already provides for the data redundancy. Also, if you stripe across disks, you're liable to be as slow as the slowest of your disks, so data nodes are typically configured to point to multiple disks. -- Philip
