Hi, Also, please make it a point to use only hostnames in your configuration also. Hadoop works entirely on hostname configurations.
Thanks Sudhan S On Fri, Nov 4, 2011 at 9:39 PM, Russell Brown <misterr...@gmail.com> wrote: > Done so, working, Awesome and many many thanks! > > Cheers > > Russell > On 4 Nov 2011, at 16:06, Uma Maheswara Rao G 72686 wrote: > > > ----- Original Message ----- > > From: Russell Brown <misterr...@gmail.com> > > Date: Friday, November 4, 2011 9:18 pm > > Subject: Re: Never ending reduce jobs, error Error reading task > outputConnection refused > > To: mapreduce-user@hadoop.apache.org > > > >> > >> On 4 Nov 2011, at 15:44, Uma Maheswara Rao G 72686 wrote: > >> > >>> ----- Original Message ----- > >>> From: Russell Brown <misterr...@gmail.com> > >>> Date: Friday, November 4, 2011 9:11 pm > >>> Subject: Re: Never ending reduce jobs, error Error reading task > >> outputConnection refused > >>> To: mapreduce-user@hadoop.apache.org > >>> > >>>> > >>>> On 4 Nov 2011, at 15:35, Uma Maheswara Rao G 72686 wrote: > >>>> > >>>>> This problem may come if you dont configure the hostmappings > >>>> properly.> Can you check whether your tasktrackers are pingable > >>>> from each other with the configured hosts names? > >>>> > >>>> > >>>> Hi, > >>>> Thanks for replying so fast! > >>>> > >>>> Hostnames? I use IP addresses in the slaves config file, and > >> via > >>>> IP addresses everyone can ping everyone else, do I need to set > >> up > >>>> hostnames too? > >>> Yes, can you configure hostname mappings and check.. > >> > >> Like full blown DNS? I mean there is no reference to any machine > >> by hostname in any of my config anywhere, so I'm not sure where to > >> start. These machines are just on my local network. > > you need to configure them in /etc/hosts file. > > ex: xx.xx.xx.xx1 TT_HOSTNAME1 > > xx.xx.xx.xx2 TT_HOSTNAME2 > > xx.xx.xx.xx3 TT_HOSTNAME3 > > xx.xx.xx.xx4 TT_HOSTNAME4 > > configure them in all the machines and check. > >> > >>>> > >>>> Cheers > >>>> > >>>> Russell > >>>>> > >>>>> Regards, > >>>>> Uma > >>>>> ----- Original Message ----- > >>>>> From: Russell Brown <misterr...@gmail.com> > >>>>> Date: Friday, November 4, 2011 9:00 pm > >>>>> Subject: Never ending reduce jobs, error Error reading task > >>>> outputConnection refused > >>>>> To: mapreduce-user@hadoop.apache.org > >>>>> > >>>>>> Hi, > >>>>>> I have a cluster of 4 tasktracker/datanodes and 1 > >>>>>> JobTracker/Namenode. I can run small jobs on this cluster > >> fine > >>>>>> (like up to a few thousand keys) but more than that and I > >> start > >>>>>> seeing errors like this: > >>>>>> > >>>>>> > >>>>>> 11/11/04 08:16:08 INFO mapred.JobClient: Task Id : > >>>>>> attempt_201111040342_0006_m_000005_0, Status : FAILED > >>>>>> Too many fetch-failures > >>>>>> 11/11/04 08:16:08 WARN mapred.JobClient: Error reading task > >>>>>> outputConnection refused > >>>>>> 11/11/04 08:16:08 WARN mapred.JobClient: Error reading task > >>>>>> outputConnection refused > >>>>>> 11/11/04 08:16:13 INFO mapred.JobClient: map 97% reduce 1% > >>>>>> 11/11/04 08:16:25 INFO mapred.JobClient: map 100% reduce 1% > >>>>>> 11/11/04 08:17:20 INFO mapred.JobClient: Task Id : > >>>>>> attempt_201111040342_0006_m_000010_0, Status : FAILED > >>>>>> Too many fetch-failures > >>>>>> 11/11/04 08:17:20 WARN mapred.JobClient: Error reading task > >>>>>> outputConnection refused > >>>>>> 11/11/04 08:17:20 WARN mapred.JobClient: Error reading task > >>>>>> outputConnection refused > >>>>>> 11/11/04 08:17:24 INFO mapred.JobClient: map 97% reduce 1% > >>>>>> 11/11/04 08:17:36 INFO mapred.JobClient: map 100% reduce 1% > >>>>>> 11/11/04 08:19:20 INFO mapred.JobClient: Task Id : > >>>>>> attempt_201111040342_0006_m_000011_0, Status : FAILED > >>>>>> Too many fetch-failures > >>>>>> > >>>>>> > >>>>>> > >>>>>> I have no IDEA what this means. All my nodes can ssh to each > >>>>>> other, pass wordlessly, all the time. > >>>>>> > >>>>>> On the individual data/task nodes the logs have errors like this: > >>>>>> > >>>>>> 2011-11-04 08:24:42,514 WARN > >>>> org.apache.hadoop.mapred.TaskTracker: > >>>>>> getMapOutput(attempt_201111040342_0006_m_000015_0,2) failed : > >>>>>> org.apache.hadoop.util.DiskChecker$DiskErrorException: Could > >>>> not > >>>>>> find > >>>> > >> > taskTracker/vagrant/jobcache/job_201111040342_0006/attempt_201111040342_0006_m_000015_0/output/file.out.index > in any of the configured local directories > >>>>>> at > >>>>>> > >>>> > >> > org.apache.hadoop.fs.LocalDirAllocator$AllocatorPerContext.getLocalPathToRead(LocalDirAllocator.java:429) > at > org.apache.hadoop.fs.LocalDirAllocator.getLocalPathToRead(LocalDirAllocator.java:160) > >>>>>> at > >>>>>> > >>>> > >> > org.apache.hadoop.mapred.TaskTracker$MapOutputServlet.doGet(TaskTracker.java:3543) > at javax.servlet.http.HttpServlet.service(HttpServlet.java:707) > >>>>>> at javax.servlet.http.HttpServlet.service(HttpServlet.java:820) > >>>>>> at > >>>>>> > >>>> > >> org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511) > at > org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221) > >>>>>> at > >>>>>> > >>>> > >> > org.apache.hadoop.http.HttpServer$QuotingInputFilter.doFilter(HttpServer.java:816) > at > org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212) > >>>>>> at > >>>>>> > >>>> > >> > org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399) > at > org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) > >>>>>> at > >>>>>> > >>>> > >> > org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182) > at > org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:766) > >>>>>> at > >>>>>> > >>>> > >> org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450) > at > org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230) > >>>>>> at > >>>>>> > >>>> > >> > org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) > at org.mortbay.jetty.Server.handle(Server.java:326) > >>>>>> at > >>>>>> > >>>> > >> org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542) > at > org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:928) > >>>>>> at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549) > >>>>>> at > >>>> > >> org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)>> > >>>> at > >> org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)>>>> > at > >>>>>> > >>>> > >> > org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410) > at > org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582) > >>>>>> > >>>>>> 2011-11-04 08:24:42,514 WARN > >>>> org.apache.hadoop.mapred.TaskTracker: > >>>>>> Unknown child with bad map output: > >>>>>> attempt_201111040342_0006_m_000015_0. Ignored. > >>>>>> > >>>>>> > >>>>>> Are they related? What d any of the mean? > >>>>>> > >>>>>> If I use a much smaller amount of data I don't see any of > >> these > >>>>>> errors and everything works fine, so I guess they are to do > >>>> with > >>>>>> some resource (though what I don't know?) Looking at > >>>>>> MASTERNODE:50070/dfsnodelist.jsp?whatNodes=LIVE > >>>>>> I see that datanodes have ample disk space, that isn't it… > >>>>>> > >>>>>> Any help at all really appreciated. Searching for the errors > >> on > >>>>>> Google has me nothing, reading the Hadoop definitive guide as > >>>> me > >>>>>> nothing. > >>>>>> Many thanks in advance > >>>>>> > >>>>>> Russell > >>>> > >>>> > >>> Regards, > >>> Uma > >> > >> > >
