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-----Original message-----
> From:Upayavira <u...@odoko.co.uk>
> Sent: Thu 20-Dec-2012 14:45
> To: solr-user@lucene.apache.org
> Subject: Re: Pause and resume indexing on SolR 4 for backups
>
> The backup directory should just be a clone of the index files. I'm
> curious to know whether it is a cp -r or a cp -lr that the replication
> handler produces.
>
> You would prevent commits by telling your app not to commit. That is,
> Solr only commits when it is *told* to.
>
> Unless you use autocommit, in which case I guess you could monitor your
> logs for the last commit, and do your backup a 10 seconds after that.
>
> Upayavira
>
> On Thu, Dec 20, 2012, at 12:44 PM, Andy D'Arcy Jewell wrote:
> > On 20/12/12 11:58, Upayavira wrote:
> > > I've never used it, but the replication handler has an option:
> > >
> > > http://master_host:port/solr/replication?command=backup
> > >
> > > Which will take you a backup.
> > I've looked at that this morning as suggested by Markus Jelsma. Looks
> > good, but I'll have to work out how to use the resultant backup
> > directory. I've been dealing with another unrelated issue in the
> > mean-time and I haven't had a chance to look for any docu so far.
> > > Also something to note, if you don't want to use the above, and you are
> > > running on Unix, you can create fast 'hard link' clones of lucene
> > > indexes. Doing:
> > >
> > > cp -lr data data.bak
> > >
> > > will copy your index instantly. If you can avoid doing this when a
> > > commit is happening, then you'll have a good index copy, that will take
> > > no space on your disk and be made instantly. This is because it just
> > > copies the directory structure, not the files themselves, and given
> > > files in a lucene index never change (they are only ever deleted or
> > > replaced), this works as a good copy technique for backing up.
> > That's the approach that Shawn Heisey proposed, and what I've been
> > working towards, but it still leaves open the question of how to
> > *pause* SolR or prevent commits during the backup (otherwise we have a
> > potential race condition).
> >
> > -Andy
> >
> >
> > --
> > Andy D'Arcy Jewell
> >
> > SysMicro Limited
> > Linux Support
> > E: andy.jew...@sysmicro.co.uk
> > W: www.sysmicro.co.uk
> >
>
