Hadoop Namenode and ZKFC tuning

Separate port(8022) for internal communication Changing handler count for better Name node performance:

Set below parameter in hdfs-site.xml

<property> <name>dfs.namenode.servicerpc-address.mas.NomeNodeHost1-com</name> <value>NomeNodeHost1.com:8022</value> </property> <property> <name>dfs.namenode.servicerpc-address.mas.NomeNodeHost1-com</name> <value>NomeNodeHost2.com:8022</value> </property>
For 15 data nodes: ln(number of DNs)*20= 2.708*20 = 54
<property> <name>dfs.namenode.handler.count</name> <value>55</value> </property> <property> <name>dfs.namenode.service.handler.count</name> <value>55</value> <!-- For internal service communications for 8022 -> </property> Steps to refresh cluster with above changes:
1. stop hadoop-hdfs-zkfc in both systems
service hadoop-hdfs-zkfc stop
2. remove hadoop-ha in zookeeper
$zookeeper-client
>rmr /hadoop-ha
3. create hadoop-ha using below command
sudo -u hdfs hdfs zkfc -formatZK
4. start both zkfc services
service hadoop-hdfs-zkfc start
5. start name node