I hope we can get fail over to backup masters in 0.20. I know Nitay is working on the groundwork for it. No more master SPOF would be fantastic.
Also, I want to second that if the master shuts down, the regionservers will flush and exit. There is no data loss for a master failure scenario. - Andy > From: Ryan Rawson <[email protected]> > Subject: Re: Some HBase FAQ > To: [email protected] > Date: Tuesday, April 14, 2009, 12:29 AM > The write-ahead log is to recover in crash scenarios. > Even if the regionserver crashes, recovery from log > will save you. > > But even so, during a controlled shutdown, regionserver > flushes memcache -> disk. If the master dies, this > flush should get your data to persistent disk. > > On Tue, Apr 14, 2009 at 12:24 AM, Puri, Aseem wrote: > > > Actually I read that if HBase master fails cluster > > will shut down, so I think for that instance if the > > data in currently memcache will also lost.
