Apache Solr Reference Guide Covering Apache Solr 6.0

for the simplest keyword searching through to complex queries on multiple fields and faceted search results. Sea
rching has more information about searching and queries.
If Solr's capabilities are not impressive enough, its ability to handle very high-volume applications should do the
trick.
A relatively common scenario is that you have so much data, or so many queries, that a single Solr server is
unable to handle your entire workload. In this case, you can scale up the capabilities of your application using So
lrCloud to better distribute the data, and the processing of requests, across many servers. Multiple options can
be mixed and matched depending on the type of scalability you need.
For example: "Sharding" is a scaling technique in which a collection is split into multiple logical pieces called
"shards" in order to scale up the number of documents in a collection beyond what could physically fit on a single
server. Incoming queries are distributed to every shard in the collection, which respond with merged results.
Another technique available is to increase the "Replication Factor" of your collection, which allows you to add
servers with additional copies of your collection to handle higher concurrent query load by spreading the
requests around to multiple machines. Sharding and Replication are not mutually exclusive, and together make
Solr an extremely powerful and scalable platform.
Best of all, this talk about high-volume applications is not just hypothetical: some of the famous Internet sites that
use Solr today are Macy's, EBay, and Zappo's.
For more information, take a look at https://wiki.apache.org/solr/PublicServers.
A Step Closer
You already have some idea of Solr's schema. This section describes Solr's home directory and other
configuration options.
When Solr runs in an application server, it needs access to a home directory. The home directory contains
important configuration information and is the place where Solr will store its index. The layout of the home
directory will look a little different when you are running Solr in standalone mode vs when you are running in
SolrCloud mode.
The crucial parts of the Solr home directory are shown in these examples:
Standalone Mode
/
solr.xml
core_name1/
core.properties
conf/
solrconfig.xml
managed-schema
data/
core_name2/
core.properties
conf/
solrconfig.xml
managed-schema
data/
Apache Solr Reference Guide 6.0
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