Find the IP address of the client in an SSH session

Check if there is an environment variable called:

$SSH_CLIENT 

OR

$SSH_CONNECTION

(or any other environment variables) which gets set when the user logs in. Then process it using the user login script.

Extract the IP:

$ echo $SSH_CLIENT | awk '{ print $1}'
1.2.3.4
$ echo $SSH_CONNECTION | awk '{print $1}'
1.2.3.4

Try the following to get just the IP address:

who am i|awk '{ print $5}'

You could use the command:

server:~# pinky

that will give to you somehting like this:

Login      Name                 TTY    Idle   When                 Where 

root       root                 pts/0         2009-06-15 13:41     192.168.1.133