thanks so much Matt. your solution works cleanly
On Wed, May 11, 2011 at 5:27 PM, Matthew Foley <ma...@yahoo-inc.com> wrote: > The cleanest way to do this repeatably is to use the --config option of the > launch scripts. > Copy the whole $HADOOP_CONF_DIR to a second directory, and edit > hdfs-site.xml (and any other config files desired) as you please. > Pass one to the NN, and one to the Backup NN: > > $HADOOP_COMMON_HOME/bin/hadoop-daemon.sh --config <conf_dir_1> --script > $HADOOP_HDFS_HOME/bin/hdfs start namenode > $HADOOP_COMMON_HOME/bin/hadoop-daemon.sh --config <conf_dir_2> --script > $HADOOP_HDFS_HOME/bin/hdfs start namenode -backup > > The $HADOOP_HDFS_HOME/bin/hdfs script will also accept the --config option, > if you prefer not to launch as a daemon. > Invoke bin/hdfs without any command line arguments, and it will show the > usage. > > Note that it is usually not advised to run two Namenodes in a single server > because of memory contention. But if you have a modest sized namespace and > a lot of ram, it may be okay. > > --Matt > > > On May 11, 2011, at 1:06 PM, Thanh Do wrote: > > thanks! this works. > but we need to play a ugly trick. > > Is there any way to run the BackupNode > with different config directory? > > The current way to start backup node is: > bin/hdfs namenode -backup > > But this doesn't provide a way to specify > the config directory. > > On Mon, May 9, 2011 at 8:33 PM, Ozcan ILIKHAN <ilik...@cs.wisc.edu> wrote: > >> Since they are using different ports, I donot think there will be a >> problem. Only problem can arise because of namespace directory. I did not >> tested but should work in following steps: >> 1- Start NameNode. >> 2- change dfs.name.dir in hdfs-site.xml >> 3- start BackupNode >> >> >> *From:* Thanh Do <than...@cs.wisc.edu> >> *Sent:* Monday, May 09, 2011 8:06 PM >> *To:* hdfs-user@hadoop.apache.org >> *Subject:* running backup node in the same host as namenode >> >> hi all, >> >> I am using hdfs 0.21.0, and want to run >> Backup Node in the same host as the NameNode >> for experiment purpose. >> >> Can anyone shed some light on how to do that? >> >> Many thanks, >> Thanh >> > > >
