I can see all daemons running when I run jps.
On master:
37282 DataNode
39393 SecondaryNameNode
44839 NameNode
99821 ResourceManager
28384 NodeManager
11238 JobHistoryServer
On slave:
23823 Jps
38482 NodeManager
48839 DataNode
But I can not find slave on my web UI. I can only see the master.