One more question for the FAQ: 6. Is it possible for an admin to tell just how out of sync the two clusters are? Something like Seconds_Behind_Master in MySQL's SHOW SLAVE STATUS?
On Wed, Mar 2, 2011 at 9:32 PM, Jean-Daniel Cryans <[email protected]> wrote: > Although, I would add that this feature is still experimental so who knows :) > > I think the worst that happened to us was that replication was broken > (see the jira where if the master loses it's zk session with the slave > zk ensemble, it requires a HBase restart on the master side) for a few > days because of maintenance of the link between the two datacenters > which took more than a minute. When we finally did restart the master > cluster, it had to process about 2TBs of HLogs... those ICVs can > really generate a lot of data! > > J-D > > On Wed, Mar 2, 2011 at 9:25 PM, Jean-Daniel Cryans <[email protected]> > wrote: >>> 5. If one is adding replication on the *production* Master cluster, what's >>> the >>> worst thing that can happen to this Master cluster? Nothing scary other >>> than >>> changing configs + interruption during a restart? (which is currently still >>> bad >>> because of region assignments?) >>> >> >> The replication code is pretty much encapsulated from the rest of the >> region server code, it won't mess with your Puts or change your >> birthday date. >> >> With 0.90 the regions are reassigned where they were before, so it's >> really just the block cache that gets screwed. >> >> J-D >> >
