问题
i have successfully installed ubuntu 12.04 and hadoop 2.3.0.
after entering the jps command i find the output as below
4135 jps
2582 SeconadaryNameNode
3143 NodeManager
2394 Namenode
2391 Datanode
3021 ResourceManager
why it is not showing the jobtracker and tasktracker. i tried start-mapred.sh but it shows command not found.(i searched the hadoop directory no such file found so i think the newer version i.e 2.0.3 has deprecated it and must be having some other way of starting jobtracker and tasktracker)
localhost:50070 working absolutely fine but localhost:50030 and localhost:50060 shows unable to connect.
so anybody can help me out in this?
回答1:
You have installed the Hadoop 2.x with YARN. The Jobtracker and Tasktracker is replaced now with NodeManager,ResourceManager and Application Master. More Information about YARN (MRv2).
http://hadoop.apache.org/docs/r2.3.0/hadoop-yarn/hadoop-yarn-site/YARN.html
回答2:
To monitor the YARN based hadoop system you can use its WebUI which can be found at:
localhost:8088
Also If u want to view the stats regarding the jobs executed or view the logs generated you have to start the jobhistory server. It can be started by following command:
mr-jobhistory-daemon.sh start history server
Once the history server is started you can view the logs generated at a single place. You can access history server at
localhost:19888
回答3:
I believe your command to start the jobhistory server is slightly off. No space between the word history and server. My command was: /usr/local/hadoop/sbin/mr-jobhistory-daemon.sh start historyserver. /sbin vs. /bin is due to my version of Hadoop.
来源：https://stackoverflow.com/questions/23978391/jobtracker-and-tasktracker-not-opening