On 5/7/2015 3:04 AM, Vincenzo D'Amore wrote: > Thanks Erick. I'm not sure I got your answer. > > I try to recap, when the raw document has to be indexed, it will be > forwarded to shard leader. Shard leader indexes the document for that > shard, and then forwards the indexed document to any replicas. > > I want just be sure that when the raw document is forwarded from the leader > to the replicas it will be indexed only one time on the shard leader. From > what I understand replicas do not indexes, only the leader indexes.
The document is indexed by all replicas. There is no way to forward the indexed document, it can only forward the source document ... so each replica must index it independently. The old-style master-slave replication (which existed long before SolrCloud) copies the finished Lucene segments, so only the master actually does indexing. SolrCloud doesn't have a master, only multiple replicas, one of which is elected leader, and replication only comes into the picture if there's a serious problem and Solr determines that it can't use the transaction log to recover the index. Thanks, Shawn
