On 2/13/2016 6:01 PM, McCallick, Paul wrote: > - When creating a new collection, SOLRCloud will use all available nodes for > the collection, adding cores to each. This assumes that you do not specify a > replicationFactor.
The number of nodes that will be used is numShards multipled by replicationFactor. The default value for replicationFactor is 1. If you do not specify numShards, there is no default -- the CREATE call will fail. The value of maxShardsPerNode can also affect the overall result. > - When adding new nodes to the cluster AFTER the collection is created, one > must use the core admin api to add the node to the collection. Using the CoreAdmin API is strongly discouraged when running SolrCloud. It works, but it is an expert API when in cloud mode, and can cause serious problems if not used correctly. Instead, use the Collections API. It can handle all normal maintenance needs. > I would really like to see the second case behave more like the first. If I > add a node to the cluster, it is automatically used as a replica for existing > clusters without my having to do so. This would really simplify things. I've added a FAQ entry to address why this is a bad idea. https://wiki.apache.org/solr/FAQ#Why_doesn.27t_SolrCloud_automatically_create_replicas_when_I_add_nodes.3F Thanks, Shawn
