# Access a Remote Shell with OpenSSH

# Prerequisites

Linux is installed and a user(s) has been created
If using a virtual machine, port 22 is forwarded

# Install OpenSSH on the Server

OpenSSH server may already be installed on your server. Get the status of the sshd service to check.

systemctl status sshd

If you see output that starts with something like the following, OpenSSH server is already installed and running. You can safely skip to the next section, Install OpenSSH on the Client.

ssh.service - OpenBSD Secure Shell server
     Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled)
     Active: active (running) since Tue 2023-05-02 11:11:20 CDT; 10min ago

If instead, you see an error like the following, OpenSSH server is not installed.

Unit sshd.service could not be found.

In that case, install OpenSSH server.

sudo apt update
sudo apt install -y openssh-server

# Install OpenSSH on the Client

To connect to your server via OpenSSH, you will need to have the client installed on the workstation you want to connect from.

You may already have it installed. Try running ssh from a terminal.

If you see output that starts with something like the following, OpenSSH client is already installed and you can safely skip to the next section, Connect.

usage: ssh [-46AaCfGgKkMNnqsTtVvXxYy] [-B bind_interface]

Otherwise, if you receive an error message, you must install OpenSSH client. The process will depend on your operating system.

Open Settings > Apps > Optional Features
Search for OpenSSH Client
Select Install

Install OpenSSH client using your package manager. For example, if you're using Debian Linux, run:

sudo apt update
sudo apt install -y openssh-client

# Connect

On your workstation machine (not the server), open up a Terminal.

If you're using a virtual machine, you can also connect to the server from the host machine.

Connect to the server via SSH.

ssh [your username]@[your server's IP address/hostname]

Be sure to replace [your username] with your actual username on the server and replace [your server's IP address/hostname] with your server's actual IP address or hostname.

You may use localhost as the hostname if...

you're using a virtual machine,
you're connecting from the host machine, and
you have port 22 forwarded

If you set up your SSH port to something other than 22, you must add -p [port number] to the end of the command.

If asked if you want to continue connecting, type yes and press Enter

You will be prompted for your user's password on the server. Enter it and press Enter.

You are now logged in to your server remotely via SSH.

While using password authentication with OpenSSH like this is convenient, you may consider the added benefits of configuring public key authentication.