On 19/02/14 07:57, Vineet Mishra wrote:
Thanks for all your response but my doubt is which *Server:Port* should the
query be made as we don't know the crashed server or which server might
crash in the future(as any server can go down).
That is what CloudSolrServer will deal with for you. It knows which
servers are down and make sure not to send request to those servers.
The only intention for writing this doubt is to get an idea about how the
query format for distributed search might work if any of the shard or
replica goes down.
// Setting up your CloudSolrServer-client
CloudSolrServer client= new CloudSolrServer(<zkConnectionStr>); //
<zkConnectionStr> being the same string as you provide in -D|zkHost when starting
your servers
|client.setDefaultCollection("collection1");
client.connect();
// Creating and firing queries (you can do it in different way, but at least
this is an option)
SolrQuery query = new SolrQuery("*:*");
QueryResponse results = client.query(query);
Because you are using CloudSolrServer you do not have to worry about not
sending the request to a crashed server.
In your example I believe the situation is as follows:
* One collection called "collection1" with two shards "shard1" and
"shard2" each having two replica "replica1" and "replica2" (a replica is
an "instance" of a shard, and when you have one replica you are not
having replication).
* collection1.shard1.replica1 is running on localhost:8983 and
collection1.shard1.replica2 is running on localhost:8900 (or maybe switched)
* collection1.shard2.replica1 is running on localhost:7574 and
collection1.shard2.replica2 is running on localhost:7500 (or maybe switched)
If localhost:8900 is the only server that is down, all data is still
available for search because every shard has at least on replica
running. In that case I believe setting "shards.tolerant" will not make
a difference. You will get your response no matter what. But if
localhost:8983 was also down there would no live replica of shard1. I
that case you will get an exception from you query, indicating that the
query cannot be carried out over the complete data-set. In that case if
you set "shards.tolerant" that behaviour will change, and you will not
get an exception - you will get a real response, but it will just not
include data from shard1, because it is not available at the moment.
That is just the way I believe "shards.tolerant" works, but you might
want to verify that.
To set "shards.tolerant":
SolrQuery query = new SolrQuery("*:*");
query.set("shards.tolerant", true);
QueryResponse results = client.query(query);
Believe distributes search is default, but you can explicitly require it by
query.setDistrib(true);
or
query.set("distrib", true);
Thanks
