The ReplicationHandler (http://wiki.apache.org/solr/SolrReplication) has support for "backups", which can be triggered in one of two ways:
1. in response to startup/commit/optimize events (specified through the backupAfter tag specified in the handler's requestHandler tag in solrconfig.xml) 2. by manually hitting http://master_host:port/solr/replication?command=backup These backups get placed in directories named, e.g. "snapshot.20090924033521", inside the solr data directory. According to the docs, these backups are not necessary for replication to work. My question is: What use case *are* they meant to address? The first potential use case that came to mind was that maybe I would be able to restore my index from these snapshot directories should it ever become corrupted. (I could just do something like "rm -r data; mv snapshot.20090924033521 data".) That appears not to be one of the intended use cases, though; if it were, then I imagine the snapshot directories would contain the entire index, whereas they seem to contain only deltas of one form or another. Thanks, Chris
