I found that there is no master znode under /hbase in zookeeper. Actually, the /hbase directory is not even created after just start the master (Based on Log and webUI, the master is up fine). After I bring up a RS, the /hbase directory and some other znode like /hbase/backup-masters, /hbase/online-snapshot, ... and created, but still no /hbase/master.
Anyone has any idea why? Without /hbase/master znode, RS/client won't be able to find the master.