hadoop namenode not starting/formatting on Ubuntu

The reason you are seeing the error message is because of command typo, that is why namenode class is showing the Usage error, may be you have issued the command option improperly.

Make sure you type the command properly:

bin/hadoop namenode -format

and then try to start the NameNode, you could start NameNode service on foreground just to see if everything is working out properly and if you don't see any errors you could kill the process and start all the services using start-all.sh script.

Here's how you could start NameNode process on foreground:

bin/hadoop namenode

once started these are the log messages to look for to validate a proper startup:

15/02/04 10:42:44 INFO http.HttpServer: Jetty bound to port 5007015/02/04 10:42:44 INFO mortbay.log: jetty-6.1.2615/02/04 10:42:45 INFO mortbay.log: Started SelectChannelConnector@0.0.0.0:5007015/02/04 10:42:45 INFO namenode.NameNode: Web-server up at: 0.0.0.0:5007015/02/04 10:42:45 INFO ipc.Server: IPC Server Responder: starting15/02/04 10:42:45 INFO ipc.Server: IPC Server listener on 8020: starting15/02/04 10:42:45 INFO ipc.Server: IPC Server handler 0 on 8020: starting15/02/04 10:42:45 INFO ipc.Server: IPC Server handler 1 on 8020: starting15/02/04 10:42:45 INFO ipc.Server: IPC Server handler 2 on 8020: starting15/02/04 10:42:45 INFO ipc.Server: IPC Server handler 3 on 8020: starting15/02/04 10:42:45 INFO ipc.Server: IPC Server handler 4 on 8020: starting15/02/04 10:42:45 INFO ipc.Server: IPC Server handler 5 on 8020: starting15/02/04 10:42:45 INFO ipc.Server: IPC Server handler 6 on 8020: starting15/02/04 10:42:45 INFO ipc.Server: IPC Server handler 7 on 8020: starting15/02/04 10:42:45 INFO ipc.Server: IPC Server handler 8 on 8020: starting15/02/04 10:42:45 INFO ipc.Server: IPC Server handler 9 on 8020: starting

you could kill the service by sending <Ctrl+C> to the process.