Distributed solr is simply the ability for Solr to take the incoming query and send it to multiple shards, then aggregate the response. Here a "shard" is a physical partition of a single logical index. The assumption is that you can't fit the entire index on a single machine and still get the performance you need, so you use N smaller "parts".
So, there has to be some mechanism to send the request to each sub-index and assemble the response and give it back to the client. That's "distrubuted solr". Before 4.0, splitting the index up was entirely manual, _you_ decided what document went to what shard. _you_ configured Solr to "know" about where the other shards were. _you_ handled the situation where a node went down and you had to "heal" the network. But it was still using "distributed search" As of 4.0, SolrCloud happens. The differences are 1> you can have Solr automatically distribute the docs to the right shard. 2> when a node goes down, Solr can automatically compensate (assuming more than one replica/shard) 3> when the node comes back up, Solr will automatically re-synchronize the node before (automatically) bringing it back into service NOTE: you can still use old-style manual sharding if you choose, it's available in 4.x But be careful here and draw a distinction between "distributed search" and "federated search". Distributed search - what we've been talking about, the underlying assumption is that the sub-indexes are all substantially similar. Federated search - the sub-indexes (or, indeed, complete self-contained indexes) may have no relation to each other and you're somehow expected to search them all and return the results. In this case you'll probably be firing off N separate queries (one to each of N indexes) and assembling them at the app layer. Best, Erick On Sun, Mar 30, 2014 at 1:42 PM, Priti Solanki <pritiatw...@gmail.com> wrote: > Hello Member, > > Is there any difference between distributed solr & solrCloud ? > > Consider I have three countries' product. I have indexed one country data > and it's index size is 160 gb+ > > Now we have other two countries and now I am confused ! > > My client ask me what is the difference if we procure another Solr server > and indexed separately....I was thinking for solrcloud.Can someone explain > how we can explain these two approaches in simple words and if there are > any reading links please share. > > Thanks
