Install the openssh-server
to perform an installation of the SSH server on your Ubuntu 20.04 system:
$ sudo apt install openssh-server
Check the status. After the SSH server package installation the SSH server daemon should be up and running. To check the status of your SSH server execute the following command:
$ systemctl status sshd
To start
, stop
and restart
your SSH server uses the systemctl
command. For example, the below command will restart
the SSH server daemon:
$ sudo systemctl restart ssh
Open SSH port 22 for incoming traffic on your firewall:
$ sudo ufw allow ssh
Enable the SSH server to start automatically during the boot.
$ sudo systemctl enable ssh
Connect from a remote client to your SSH server. First, obtain an IP address of your SSH server. To do so execute the bellowip
command:
$ ip a
In case you wish to connect to your SSH server over the internet you will need to obtain your external IP address:
$ echo $(wget -qO - https://api.ipify.org)
Lastly, connect to your SSH server remotely using the following SSH command syntax ssh username@hostname-or-ip-address
.
For example, the bellow command will connect to the Ubuntu 20.04 SSH server with an IP address 192.168.1.112
as a user linuxconfig
:
$ ssh [email protected]
(optional) From security reasons it is recommended to change the default SSH port22
to some other arbitrary port number above 1024. To do so edit the/etc/ssh/sshd_config
configuration file as an administrative sudo user.
For example to change the default SSH port number from 22
to eg. 8282
add the following line to the SSH config file:
Port 8282
Once you have made the appropriate change open a firewall port to correspond with the new SSH port:
$ sudo ufw allow 8282/tcp
To apply the change to your SSH server use systemctl
command to restart it:
$ sudo systemctl restart ssh
To remotely connect to a specific SSH Server port number use the -p
ssh command line option. Example:
$ ssh -p 8282 [email protected]