How to install ssh in ubuntu

To install and enable SSH on Ubuntu, you need to install the openssh-server package.

Step-by-Step Installation

1. Open the terminal application on your Ubuntu system (usually by pressing Ctrl + Alt + T or searching for “Terminal” in the applications menu).
2. Update your package lists to ensure you can download the latest version of the software:

bash

sudo apt update

1. You can optionally run sudo apt upgrade to update existing packages.
2. Install the OpenSSH server package by running the following command:bashsudo apt install openssh-server Enter your password when prompted and press Enter to confirm the installation. The SSH service will start automatically once installation is complete.
3. Verify the SSH service status to confirm it is running:bashsudo systemctl status ssh The output should show Active: active (running). It should also be enabled to start automatically on system boot.
4. Adjust the firewall (if active) to allow incoming SSH traffic on its default port (22):bashsudo ufw allow ssh sudo ufw enable The sudo ufw allow ssh command uses a built-in application
5. profile for SSH. Use sudo ufw status to verify the rule has been added correctly
6. How to Connect to Your Ubuntu System

From another computer (client), you can connect using the ssh command followed by your username and the IP address of the Ubuntu machine where you installed the server: 

bash

ssh username@server-ip-address

• Linux/macOS: The ssh client is usually pre-installed.
• Windows: You can use the built-in Windows Terminal or a third-party client like Putty

Next Steps (Security Best Practices)

For enhanced security, especially if your server is accessible from the internet, consider the following: 

• Set up SSH key-based authentication to log in without a password.
• Disable password authentication in the SSH configuration file (/etc/ssh/sshd_config) once key-based login is working.
• Change the default SSH port from 22 to a non-standard port to reduce automated attack attempts.
• Disable direct root login via SSH in the configuration file by setting PermitRootLogin no. 

Remember to restart the SSH service after making any changes to the configuration file using sudo systemctl restart ssh