Dear Wiki user, You have subscribed to a wiki page or wiki category on "Hadoop Wiki" for change notification.
The following page has been changed by stack: http://wiki.apache.org/hadoop/Hbase/Troubleshooting ------------------------------------------------------------------------------ === Causes === * Slow datanodes are marked as down by DFSClient; eventually all replicas are marked as 'bad' (HADOOP-3831). === Resolution === - * Try setting '''dfs.datanode.socket.write.timeout''' to zero. See the thread at [http://mail-archives.apache.org/mod_mbox/hadoop-hbase-user/200810.mbox/%[email protected]%3e message from jean-adrien] for some background. Note, this is an hdfs client configuration so needs to be available in $HBASE_HOME/conf. Making the change only in $HADOOP_HOME/conf is not sufficient. Copy your amended hadoop-site.xml to the hbase conf directory or add this configuration to $HBASE_HOME/conf/hbase-site.xml. + * Try setting '''dfs.datanode.socket.write.timeout''' to zero (in hadoop 0.18.x -- See HADOOP-3831 for detail and why not needed in hadoop 0.19.x). See the thread at [http://mail-archives.apache.org/mod_mbox/hadoop-hbase-user/200810.mbox/%[email protected]%3e message from jean-adrien] for some background. Note, this is an hdfs client configuration so needs to be available in $HBASE_HOME/conf. Making the change only in $HADOOP_HOME/conf is not sufficient. Copy your amended hadoop-site.xml to the hbase conf directory or add this configuration to $HBASE_HOME/conf/hbase-site.xml. * Try increasing '''dfs.datanode.handler.count''' from its default of 3. This is a server configuration change so must be made in $HADOOP_HOME/conf/hadoop-site.xml. Try increasing it to 10, then by additional increments of 10. It probably does not make sense to use a value larger than the total number of nodes in the cluster.
