Restart task tracker and job tracker service (task tracker and job tracker) in CDH4

Question

How do I restart the task trackers and job tracker using CDH4 from the command line?

I tried following given script but got error

[root@adc1210765 bin]# ./stop-mapred.sh /usr/lib/hadoop-0.20-mapreduce/bin/../conf no jobtracker to stop cat: /usr/lib/hadoop-0.20-mapreduce/bin/../conf/slaves: No such file or directory

I want to restart all instance of tasktracker running at my cluster nodes

Answer 1

You must do this on each of the task trackers

sudo service hadoop-0.20-mapreduce-tasktracker restart

And on the job tracker

sudo service hadoop-0.20-mapreduce-jobtracker restart

You can also use stop and start in place of restart. Might have to change your hadoop version number.

http://www.cloudera.com/content/cloudera-content/cloudera-docs/CDH4/latest/CDH4-Installation-Guide/cdh4ig_topic_11_3.html?scroll=topic_11_3

Answer 2

You can also try starting the JobTracker Daemon by

/etc/init.d/hadoop-0.20-mapreduce-jobtracker start

and Task Tracker by

/etc/init.d/hadoop-0.20-mapreduce-tasktracker start

Ensure the version number is appropiate.