It is the default behavior. However, in my installation it has never succeeded. So, the regions never actually get re-assigned. The result is a cluster in a funky state that needs to be completely brought down and then started up again in order to recover.
I'm running on a version of HBase that is several weeks old, but I've never seen the cluster recover from a region server going on previous versions either. I'm hoping this will be fixed soon. You should see the Master making the attempt at the same time the region server goes down in the logs. In my case, it complains about this: "java.io.IOException: cannot get log writer" caused by this "java.io.FileNotFoundException: Parent path is not a directory". FYI, Matthew On Sep 26, 2010, at 11:23 PM, Andrey Timerbaev wrote: > Stanislaw Kogut <sko...@...> writes: > >> In case when one of regionservers fail, HBase Master will reassign all >> regions, so, any regions served by failed regionserver will be >> assigned to operating regionservers. It is possible because of >> replication on datanodes, regionserver heartbeats and >> Write-Ahead-Logs. HBase master can be made redundant too. > > Hello Stanislaw, > > This is a good news. Is a particular setting needed to do HBase behave in the > redundant manner, or is it an out-of-box behavior? (In my installation I > didn't > notice namely, that HBase reassigns the regions.) > > Thank you, > Andrey > > > >
