Database Reference
In-Depth Information
1. Stop all Hadoop daemons from
hduser
using the following command on every
node:
$ for x in 'cd /etc/init.d; ls hadoop*'; do sudo
service $x stop ; done
2. Install the namenode package from
hduser
on the node you want to configure
as standby. As per our configuration, it is
node2.hcluster
.
$ sudo yum install hadoop-hdfs-namenode
3. If you are using the Quorum-based storage approach, install the JournalNode
package from
hduser
on the nodes you want to use as JournalNodes. As per our
configuration, we would need to install the JournalNode package on
node3.hcluster
,
node4.hcluster
, and
node5.hcluster
:
$ sudo yum install hadoop-hdfs-journalnode
This step can be skipped if you are using the Shared Storage approach.
4. Start the JournalNode daemon using the following command on all the nodes
where they will run:
sudo service hadoop-hdfs-journalnode start
In our configuration, the nodes are
node3.hcluster
,
node4.hcluster
,
and
node5.hcluster
.
5. Next, go to the primary namenode and execute the following command from
hd-
user
to initialize the shared edits directory from the local namenode edits direct-
ory:
$ sudo -u hdfs hdfs namenode -initializeSharedEdits
6. Next, start the primary namenode from
hduser
using the following command:
$ sudo service hadoop-hdfs-namenode start
7. Start the standby namenode from
hduser
using the following command:
$ sudo -u hdfs hdfs namenode -bootstrapStandby
$ sudo service hadoop-hdfs-namenode start
