@ Nitesh , Jeff & Ed Thanks guys !! It was a mistake in the configuration file !! It works now ! ..
8408 Jps 8109 DataNode 8370 TaskTracker 8204 SecondaryNameNode 8281 JobTracker Except for " TaskTracker$Child " !! On Mon, Nov 16, 2009 at 10:57 AM, Edward Capriolo <edlinuxg...@gmail.com>wrote: > On Mon, Nov 16, 2009 at 9:57 AM, Jeff Zhang <zjf...@gmail.com> wrote: > > look at the logs of job tracker, maybe you will get some clues. > > > > > > Jeff Zhang > > > > > > > > On Mon, Nov 16, 2009 at 6:45 AM, Prabhu Hari Dhanapal < > > dragonzsn...@gmail.com> wrote: > > > >> Hi all, > >> > >> I just installed Hadoop(single node cluster) and tried to start and stop > >> the > >> nodes , and it said > >> no jobtracker to stop , no namenode to stop > >> > >> however the tutorial i used suggest that jobtracker and namenodes should > >> also have started ? Why does this happen? > >> am i missing something? > >> > >> > >> > http://www.michael-noll.com/wiki/Running_Hadoop_On_Ubuntu_Linux_(Single-Node_Cluster)<http://www.michael-noll.com/wiki/Running_Hadoop_On_Ubuntu_Linux_%28Single-Node_Cluster%29> > < > http://www.michael-noll.com/wiki/Running_Hadoop_On_Ubuntu_Linux_%28Single-Node_Cluster%29 > > > >> > >> > >> had...@pdhanapa-laptop:/home/pdhanapa/Desktop/hadoop/bin$ jps > >> 20671 Jps > >> 20368 DataNode > >> 20463 SecondaryNameNode > >> > >> had...@pdhanapa-laptop:/home/pdhanapa/Desktop/hadoop/bin$ ./stop-all.sh > >> no jobtracker to stop > >> localhost: no tasktracker to stop > >> no namenode to stop > >> localhost: stopping datanode > >> localhost: stopping secondarynamenode > >> > >> > >> > >> > >> -- > >> Hari > >> > > > > > The issue here is that these resources failed to start. What happens > here is as soon as the java process is started the system returns an > ok status to the script. However the processes die moments later as > they start up. > > For example if you start the namenode, script returns ok, namenode > runs and realizes its dfs.name directory is not formatted. Then it > stops. > > Generally after starting a hadoop process, tail the log it creates for > a few seconds and make sure it REALLY starts up. Really the scripts > should do more pre-startup checking, but the scripts could not test > for every possible condition that could cause hadoop not to start. > > Also for long running deamons the pid files are written to /tmp see > bin/hadoop-daemon.sh > If something is cleaning /tmp stop arguments are unable to find the pid. > > That is shell scripting for you :) > Edward > -- Hari
