The base algorithm for searches picks out one replica from each shard in a round-robin fashion, without regard to whether it’s on the same machine or not.
You can alter this behavior, see: https://lucene.apache.org/solr/guide/8_1/distributed-requests.html When you say “the exact same search”, it isn’t quite in the sense that it’s going to a different shard as evidenced by &DISTRIB=false being on the URL (I’d guess you already know that, but…). The top-level request _may_ be forwarded as is, there’s an internal load balancer that does this. The theory is that all the top-level requests shouldn’t be handled by the same Solr instance if a client is directly using the http address of a single node in the cluster for all requests. Best, Erick > On May 27, 2020, at 11:12 AM, Odysci <ody...@gmail.com> wrote: > > Hi, > > I have a question regarding solrcloud searches on both replicas of an index. > I have a solrcloud setup with 2 physical machines (let's call them A and > B), and my index is divided into 2 shards, and 2 replicas, such that each > machine has a full copy of the index. My Zookeeper setup uses 3 instances. > The nodes and replicas are as follows: > Machine A: > core_node3 / shard1_replica_n1 > core_node7 / shard2_replica_n4 > Machine B: > core_node5 / shard1_replica_n2 > core_node8 / shard2_replica_n6 > > I'm using solrJ and I create the solr client using Http2SolrClient.Builder > and the IP of machineA. > > Here is my question: > when I do a search (using solrJ) and I look at the search logs on both > machines, I see that the same search is being executed on both machines. > But if the full index is present on both machines, wouldn't it be enough > just to search on one of machines? > In fact, if I turn off machine B, the search returns the correct results > anyway. > > Thanks a lot. > > Reinaldo
