Keep replicas current
You can choose from two different mechanisms for keeping replicas up to date: using a timer or using replication.
Using a Timer: In this mode, replicas are refreshed at a time interval controlled by the configuration option hbase.regionserver.storefile.refresh.period.
Using Replication: In this mode, replicas are kept current between a source and sink cluster using HBase replication. The sink clusrter in this cluster is just the read replcias in the same HBase cluster. This can potentially allow for faster synchronization than using a timer. Each time a flush occurs on the source cluster, a notification is pushed to the sink clusters for the table. To use replication to keep replicas current, you must first set the column family attribute REGION_MEMSTORE_REPLICATION to
false, then set the HBase configuration property