Pointing to some SSH tips given in Linux Magazine:
$ssh -T user@hostname
If you connect to a host this way, it will disable pseudo-tty allocation
and a command like w will not show your connection. Better add
`bash -i' , as below.
$ssh -T user@hostname /bin/bash -i
With the below command the IP address of the system you connect to wont be
logged into known_hosts file, usually its in /root/.ssh/known_hosts.
$ssh -o UserknownHostsFile=/dev/null -T user@hostname /bin/bash -i