SSH

Generate local key to access remote host

On client:

• ssh-keygen -t dsa # with empty password
• cd ~/.ssh
• cat id_dsa.pub # public key

On SSHserver:

• cd /home/userx/.ssh
• vi authorized_keys # paste the id_dsa.pub (public key) content generated on the client
• chmod 0600 authorized_keys

Login from the client with ssh userx@remote.example.org should ask for not password. Useful to invoke commands remotely using ssh

Copy file to SSH server listening on different port

scp -P 2222 filex userx@sshserver.example.org:/home/userx

Add listening ports on Ubuntu

Edit file /etc/ssh/sshd_config to set port 22 and 1234

Port 22
Port 1234

Restart service with service ssh restart