SSH is a network protocol that allows users to securely access and manage remote servers. This time, we will set up passwordless login.
Installing the OpenSSH Server
Open the terminal.
Enter the following commands to install the OpenSSH server:
sudo apt update
sudo apt install openssh-server
Check SSH Server Status
Use the following command to check the status of the SSH server:
sudo systemctl status ssh
If you see “Active: active (running),” then the SSH server has started successfully.
SSH Passwordless Login Setup:
Generate SSH Key Pair on the Client Side
Open the terminal.
Enter the following command to generate an SSH key pair:
ssh-keygen
Follow the prompts. The default settings are usually sufficient. When prompted for a passphrase, you can simply press Enter to create a key pair without a password.
Copy the Public Key to the Server
Use the ssh-copy-id command to copy the public key to the server. Replace [username] and [server-ip] with your server details.
ssh-copy-id [username]@[server-ip]
For example:
ssh-copy-id john@192.168.0.100
If your server uses a non-default SSH port (e.g., 2222), use the -p parameter:
ssh-copy-id -p 2222 john@192.168.0.100
This command will prompt you to enter the server password.
Once authentication is successful, your public key will be added to the server’s ~/.ssh/authorized_keys file.
Test Passwordless Login
Try SSH-ing into the server:
ssh [username]@[server-ip]
If everything is set up correctly, you should be able to log in to the server without a password.
Disable Password Authentication
With SSH keys configured, you may consider disabling password authentication for added security.
This can be set in the server’s /etc/ssh/sshd_config file:
sudo vim /etc/ssh/sshd_config
Find the PasswordAuthentication option in the file and set it to no.
After completing these steps, you’re ready to enjoy using SSH!