BindException java.net.BindException: Address already in use (Hadoop)

This error comes when the address with port no you have specified in Hadoop configuration is already being used by some other process, or may be other instance of Hadoop is running in some other user,

for getting information about the ip and port no you want to know you can give command as follows

netstat –nl | grep <portno> or <ip here>

This will the processing using the specific port no or IP address. for more options with netstat type on shell netstat -- help will give you all the options .

and to check if other instance of Hadoop is running type

sudo jps

this will list all the process of Hadoop running in other users.

Step by step process :

1. check which port the program is trying to bind to in the error message
2. type on the command shell: netstat -a -t --numeric-ports -p to list the ports that are in use by number and process.
3. check which process is using the port no.
4. try and identify why it is in use. Telnet <port> and pointing a web browser at it are both good tricks.
5. so either change the port no of hadoop or the other porgram that is using the port no in error message.

This method can help not in removing Exception Binding error for hadoop but also for other processes.