Thanks, Stack. 2010/6/2 Stack <[email protected]>
> On Tue, Jun 1, 2010 at 11:53 PM, Zheng Lv <[email protected]> > wrote: > > Hello All, > > We run export job to backup our hbase tables, but it takes so long time. > > Can we first stop the hbase and copy the /hbase directory as backup? If > it > > works, what if we dont stop it first? Can we just stop all the jobs > writing > > data into hbase? Thanks a lot. > > If you stop and copy the hbase.rootdir, thats a complete and truthful > copy of the data in cluster at time of shutdown. > > If you copy while its running, it'll be fuzzy at the edges since some > edits will be up in memory still. Though the in-memory edits have > been added to the WAL, you'd need a replay to get these edits back in > the mix on restore. That faciilty does not exist as yet. > > You could do take off the writes and do a force flush on the table. > Currently this facility in the shell is unfortunatley not synchronous; > i.e. it sends out the flush signal across the cluster and then returns > immediately. You'd have to do something like watch the logs on all > regionservers to see when flush had completed or just give it some > time and then do the copy. > > Related, progress is being made on hbase-50, a snapshotting facility. > Check it out if interested. A design was just posted so any comments > most welcome. > > Thanks, > St.Ack >
