private ServerName getParentRegionServerName(final MasterProcedureEnv env) {
    return env.getMasterServices().getAssignmentManager().getRegionStates()
      .getRegionServerOfRegion(getParentRegion());
  }
Post split region actions
@param env MasterProcedureEnv
hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/SplitTableRegionProcedure.java