On Feb 8, 2011, at 11:33 AM, Adam Phelps wrote: > On 2/7/11 2:06 PM, Jonathan Disher wrote: >> Currently I have a 48 node cluster using Dell R710's with 12 disks - two >> 250GB SATA drives in RAID1 for OS, and ten 1TB SATA disks as a JBOD >> (mounted on /data/0 through /data/9) and listed separately in >> hdfs-site.xml. It works... mostly. The big issues you will encounter is >> losing a disk - the DataNode process will crash, and if you comment out >> the affected drive, when you replace it you will have 9 disks full to N% >> and one empty disk. > > If DataNode is going down after a single disk failure then you probably > haven't set dfs.datanode.failed.volumes.tolerated in hdfs-site.xml. You can > up that number to allow DataNode to tolerate dead drives.
a) only if you have a version that supports it b) that only protects you on the DN side. The TT is, AFAIK, still susceptible to drive failures.
