Silly question, why are you worrying about this? In a production the odds of getting a replacement disk in service within 10 minutes after a fault is detected is highly improbable.
Why do you care that the blocks are replicated to another node? After you replace the disk, bounce the node (restart DN) (RS if running) , you can always force a rebalance of the cluster. On Nov 28, 2012, at 9:22 AM, Mark Kerzner <[email protected]> wrote: > What happens if I stop the datanode, miss the 10 min 30 seconds deadline, and > restart the datanode say 30 minutes later? Will Hadoop re-use the data on > this datanode, balancing it with HDFS? What happens to those blocks that > correspond to file that have been updated meanwhile? > > Mark > > On Wed, Nov 28, 2012 at 6:51 AM, Stephen Fritz <[email protected]> wrote: > HDFS will not start re-replicating blocks from a dead DN for 10 minutes 30 > seconds by default. > > Right now there isn't a good way to replace a disk out from under a running > datanode, so the best way is: > - Stop the DN > - Replace the disk > - Restart the DN > > > > > On Wed, Nov 28, 2012 at 9:14 AM, Mark Kerzner <[email protected]> > wrote: > Hi, > > can I remove one hard drive from a slave but tell Hadoop not to replicate > missing blocks for a few minutes, because I will return it back? Or will this > not work at all, and will Hadoop continue replicating, since I removed > blocks, even for a short time? > > Thank you. Sincerely, > Mark > >
