Run witch repair cmd when increase replication factor

I want fo increase replication factor in my C* 2.1.3 cluster(rf chang from 2 to 3 for some keyspaces). I read the doc of Updating the replication factor <http://www.datastax.com/documentation/cql/3.1/cql/cql_using/update_ks_rf_t.html> . The step two is run the nodetool repair.But as

Re: Increase replication factor

http://www.datastax.com/docs/1.0/operations/cluster_management#changing-the-replication-factor It looks like a nodetool repair is needed after increasing your RF. I guess that a cleanup has to be performed after decreasing the RF to remove useless replica. Alain 2011/12/5 A J > If I update a k

Increase replication factor

If I update a keyspace to increase the replication factor; what happens to existing data for that keyspace ? Does the existing data get automatically increase its replication ? Or only on a RR or node repair does the existing data increase its replication factor ? Thanks.