You can force the namenode to get out of safe mode: hadoop dfsadmin -safemode leave
On Tue, Aug 26, 2014 at 11:05 PM, Vincent Emonet <[email protected]> wrote: > Hello, > > We have a 11 nodes Hadoop cluster installed from Hortonworks RPM doc: > > http://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.0.9.1/bk_installing_manually_book/content/rpm-chap1.html > > The cluster was working fine since it went on Safe Mode during the > execution of a job with this message on the NameNode interface: > > > > *Safe mode is ON. Resources are low on NN. Please add or free up more > resources then turn off safe mode manually. NOTE: If you turn off safe mode > before adding resources, the NN will immediately return to safe mode. Use > "hdfs dfsadmin -safemode leave" to turn safe mode off.* > The error displayed in the job log is: > 2014-08-22 08:51:35,446 WARN namenode.NameNodeResourceChecker > (NameNodeResourceChecker.java:isResourceAvailable(89)) - Space available on > volume 'null' is 100720640, which is below the configured reserved amount > 104857600 2014-08-22 08:51:35,446 WARN namenode.FSNamesystem > (FSNamesystem.java:run(4042)) - NameNode low on available disk space. > Already in safe mode. > > On each node we have 5 hdd used for Hadoop > And we checked the 5 hdd on the namenode are all full (between 95 and > 100%) when the HDFS as still 50% of its capacity available : on the other > nodes the 5 hdd are at 30/40% > > So I think this is the cause of the error. > > On the NameNode we had some Non HDFS data on 1 hdd, so I deleted them to > have 50% of this hdd available (the 4 others are still between 95 and 100%) > But this didn't resolve the problem > I have also followed the advices found here : > https://issues.apache.org/jira/browse/HDFS-4425 > And added the following property to the hdfs-site.xml of the NameNode > (multiplying the default value by 2) > <property> > <name>dfs.namenode.resource.du.reserved</name> > <value>209715200</value> > </property> > > Still impossible to get out of the safe mode and as log as we are in safe > mode we can't delete anything in the HDFS. > > > Is anyone having a tip about this issue? > > > Thankfully, > > Vincent. > > > -- Regards, *Stanley Shi,*
