MapReduce and other Extract Translate Load (ETL) processing can be intensive, which can interfere with the ability of Cassandra to serve other requests promptly. This recipe shows how to set up a second Cassandra data center for ETL, as depicted in the following image:
Review the chapter on Multi datacenter deployments for recipes on multi-data centers setups.
Create a keyspace that is replicated three times in DC1, but only once in DC2:
[default@unknown] create keyspace ks33 with placement_strategy = 'org.apache.cassandra.locator. NetworkTopologyStrategy' and strategy_options=[{DC1:3,DC2:1}];
Open
<cassandra_home/conf/cassandra-topology.properties
in your text editor. Create an entry for each host. Put hosts 1-5 in DC1 and hosts 6-8 in DC2:10.1.2.1=DC1:rack1 #cas1 10.1.2.2=DC1:rack1 10.1.2.3=DC1:rack1 10.1.2.4=DC1:rack1 10.1.2.5=DC1:rack1 10.2.5.9=DC2:rack1 #cas6 10.2.3.4=DC2:rack1 #cas7 10...