public void addRSGroup(String groupName) throws IOException {
    AddRSGroupRequest request = AddRSGroupRequest.newBuilder().setRSGroupName(groupName).build();
    try {
      stub.addRSGroup(null, request);
    } catch (ServiceException e) {
      throw ProtobufUtil.handleRemoteException(e);
    }
  }
Creates a new RegionServer group with the given name.
hbase-server/src/main/java/org/apache/hadoop/hbase/rsgroup/RSGroupAdminClient.java