Configure core-site.xml for hadoop master slave topology(rest part)

 We have already configured hdfs-site.xml files for master and slave. Now we need to configure core-site.xml files

1. In Master or name node

in terminal

cd /etc/hadoop/

vim core-site.Xml

inside file

<property>

<name>fs.dafault.name<\name>

<value>hdfs://masterIPaddress:9001<\value >

<\property>

9001 is the port number. (You can use netstat-tnlp command which ports are in use and then

select a port which is not in use)

format the /drive which you created in master using command

hadoop name node -format

Hadoop-daemon.sh start namenode

2. In slave or data node

in terminal

cd /etc/hadoop/

vim core-site.Xml

inside file

<property>

<name>fs.dafault.name<\name>

<value>hdfs://masterIPaddress:9001<\value >

<\property>

hadoop-daemon.shstart datanode

Still it will not connect. So, for that disable firewall of master node using command

systemctl stop firewall

hadoop dfsadmin -report will check dfs report that how many slave nodes are connected to the master node