Well if it is down, it means there is an error on that particular core/instance of Solr, you would need to check the logs on that instance to see what the underlying problem is, there is no one root cause.
How to recover: fix the underlying problem and restart that Solr instance? :) With the amount of info you've given us, that's about all we can say at this stage. Could of Out Of Memory, disk space, error in a document that throws some odd exception, JVM crash, error writing to transaction log, any one of a thousand possible reasons. But that's the explanation at the high level. Each instance/solr core is a separate entity, they can crash and have problems, that's why you would normally have multiple replicas per shard, so you have redundancy. What your indexing should have noticed was that 1/3rd of your documents failed to index (since there is no server servicing shard 1, any updates to that shard will fail)! On 29 August 2013 18:37, Utkarsh Sengar <utkarsh2...@gmail.com> wrote: > bumping this one, any suggestions? > I am sure this is solrcloud 101 but I couldn't find documentation anywhere. > > Thanks, > -Utkarsh > > > On Wed, Aug 28, 2013 at 2:37 PM, Utkarsh Sengar <utkarsh2...@gmail.com > >wrote: > > > I have a 3 node solrcloud cluster with 3 shards for each collection/core. > > > > At times when I rebuild the index say on collectionA on nodeA (shard1) > via > > UpdateCSV, the "Cloud" status page says that collectionA on nodeA > (shard1) > > is down. > > > > Observations: > > 1. Other collections on nodeA work. > > 2. collectionA on nodeB and nodeC works. > > 3. nodeA's solr admin is accessible too. > > > > So my questions are: > > 1. What does it really mean when a shard goes down? > > 2. How can I recover from that state? > > > > Solr cloud screenshot: http://i.imgur.com/2TgKXiC.png > > > > -- > > Thanks, > > -Utkarsh > > > > > > -- > Thanks, > -Utkarsh >