I think I figured this out; I hope people find this useful.. It may not be possible to declare what the hash ranges are when you create the collection, but you *can* do so when you split via the 'ranges' parameter, which is a comma-delimited list. So this means you can create a new collection with one shard and then immediately split it to the desired ranges to line up with that of your backup. I also observed that if you create a collection and then split every shard (in 2), it will result in an equivalent collection to one that was created with twice as many shards to begin with. I hoped that was so and verified the ranges end up being the same both ways.
The only thing that seems like it may be benign but not 100% certain is that if you split a shard, the new shards have a 'parent' reference to the name of the shard it was split from. And even if you delete that parent shard (since it's not needed anymore; it becomes inactive). I'm not sure why this metadata is recorded because, at least after the split, I can't see why it's pertinent to anything. ~ David David Smiley (@MITRE.org) wrote > Hi, > > I'm attempting to come up with a SolrCloud restore / clone process for > either recover to a known good state or to clone the environment for > experimentation. At the moment my process involves either creating a new > zookeeper environment or at least deleting the existing Collection so that > I can create a new one. This works; I use the Core API; the first command > defines the collection parameters, and I invoke it once for each replica. > I don't use the Collection API because I want SolrCloud to go off trying > to create all the replicas -- I know where each one is pre-positioned. > > What I'm concerned about is what happens once I start wanting to use Shard > splitting, *especially* if I don't want to split all shards because shards > are uneven due to custom routing (e.g. id:"customer!myid"). In this case > I don't know how to create the collection with the hash ranges post-shard > split. Solr doesn't have an API for me to explicitly say what the hash > ranges should be on each shard (to match up with a backup). And I'm > concerned about undocumented pitfalls that may exist in manually > constructing a clusterstate.json, as another approach. > > Any ideas? > > ~ David ----- Author: http://www.packtpub.com/apache-solr-3-enterprise-search-server/book -- View this message in context: http://lucene.472066.n3.nabble.com/Clone-or-Restore-Solrcloud-tp4114773p4114983.html Sent from the Solr - User mailing list archive at Nabble.com.
