OpenSSH is a very popular SSH client/server solution, and as a result of its popularity has become the //de facto// standard for SSH servers.

===== Installation =====
==== Debian / Ubuntu ====

From a terminal enter:

''apt-get install openssh-server''

This requires root permissions, so you may need to prepend ''sudo'' to the command in order for it to successfully execute.

And you're done! If you want to change any configuration just edit "/etc/ssh/sshd_config". It is suggested that you change the port (line 5) for security purposes. If you do make any changes, run this to restart the server:

''/etc/init.d/ssh restart''

If you are connected to your machine via SSH, the above command will disconnect all users currently logged in via SSH. You will need to log in to the host machine again.

==== CentOS/RHEL ====

From a terminal enter:

''yum install openssh-server''

This requires root permissions, so you may need to first run ''su -'' in order for it to successfully execute.