HDFS is not the only useful place to send your logs and data. Solr is a popular real-time search platform used to index large amounts of data, so full text searching can be performed almost instantaneously. Hadoop's horizontal scalability creates an interesting problem for Solr, as there is now more data than a single instance can handle. For this reason, a horizontally scalable version of Solr was created, called SolrCloud. Cloudera's Search product is also based on SolrCloud, so it should be no surprise that Flume developers created a new sink specifically to write streaming data into Solr.

Like most streaming data flows, you not only transport the data, but you also often reformat it into a form more consumable to the target of the flow. Typically, this is done in a Flume-only workflow by applying one or more interceptors just prior to the sink writing the data to the target system. This sink uses the Morphline engine to transform the data, instead of interceptors.

Internally...