On disk, yes, but only indexed, and thus far enough from the original content to make storing terms in Lucene's inverted index.
Otis ---- Sematext :: http://sematext.com/ :: Solr - Lucene - Nutch Lucene ecosystem search :: http://search-lucene.com/ ----- Original Message ---- > From: Robert Petersen <rober...@buy.com> > To: solr-user@lucene.apache.org > Sent: Wed, March 9, 2011 12:07:27 PM > Subject: RE: True master-master fail-over without data gaps > > ...but the index resides on disk doesn't it??? lol > > -----Original Message----- > From: Otis Gospodnetic [mailto:otis_gospodne...@yahoo.com] > Sent: Wednesday, March 09, 2011 9:06 AM > To: solr-user@lucene.apache.org > Subject: Re: True master-master fail-over without data gaps > > Hi, > > > > ----- Original Message ---- > > > > I'd honestly think about buffer the incoming documents in some store > that's > >actually made for fail-over persistence reliability, maybe CouchDB or > something. > >And then that's taking care of not losing anything, and the problem > becomes how > >we make sure that our solr master indexes are kept in sync with the > actual > >persistent store; which I'm still not sure about, but I'm thinking it's > a > >simpler problem. The right tool for the right job, that kind of > failover > >persistence is not solr's specialty. > > > > But check this! In some cases one is not allowed to save content to > disk (think > copyrights). I'm not making this up - we actually have a customer with > this > "cannot save to disk" (but can index) requirement. > > So buffering to disk is not an option, and buffering in memory is not > practical > because of the input document rate and their size. > > Otis > ---- > Sematext :: http://sematext.com/ :: Solr - Lucene - Nutch > Lucene ecosystem search :: http://search-lucene.com/ > > > > > From: Otis Gospodnetic [otis_gospodne...@yahoo.com] > > Sent: Tuesday, March 08, 2011 11:45 PM > > To: solr-user@lucene.apache.org > > Subject: True master-master fail-over without data gaps > > > > Hello, > > > > What are some common or good ways to handle indexing (master) > fail-over? > > Imagine you have a continuous stream of incoming documents that you > have to > > index without losing any of them (or with losing as few of them as > possible). > > How do you set up you masters? > > In other words, you can't just have 2 masters where the secondary is > the > > Repeater (or Slave) of the primary master and replicates the index > >periodically: > > you need to have 2 masters that are in sync at all times! > > How do you achieve that? > > > > * Do you just put N masters behind a LB VIP, configure them both to > point to > >the > > index on some shared storage (e.g. SAN), and count on the LB to > fail-over to > >the > > secondary master when the primary becomes unreachable? > > If so, how do you deal with index locks? You use the Native lock and > count > on > > it disappearing when the primary master goes down? That means you > count on > >the > > whole JVM process dying, which may not be the case... > > > > * Or do you use tools like DRBD, Corosync, Pacemaker, etc. to keep 2 > masters > > with 2 separate indices in sync, while making sure you write to only > 1 of > them > > via LB VIP or otherwise? > > > > * Or ... > > > > > > This thread is on a similar topic, but is inconclusive: > > http://search-lucene.com/m/aOsyN15f1qd1 > > > > Here is another similar thread, but this one doesn't cover how 2 > masters are > > kept in sync at all times: > > http://search-lucene.com/m/aOsyN15f1qd1 > > > > Thanks, > > Otis > > ---- > > Sematext :: http://sematext.com/ :: Solr - Lucene - Nutch > > Lucene ecosystem search :: http://search-lucene.com/ > > > > >
