Server Access: Set Up SSH Key Authentication

Server Access: Set Up SSH Key Authentication

How to Access Server via SSH and Set Up SSH Key for Passwordless Authentication

Without setting up SSH Key, it will ask for a password each time we try to access the server.

Enhance security and convenience by establishing passwordless SSH logins using SSH key authentication. This guide explains the process of generating a key pair on your local machine, copying the public key to your server, and configuring your server to accept it.

Prerequisites

• A local machine (Windows, macOS, or Linux) with an SSH client installed.
• An SSH server running on your remote server/VPS.
• Access to both your local machine and server (SSH login credentials for the server).

To Get Access via SSH

• Syntax: ssh -p PORT USERNAME@HOSTIP
• Example: ssh -p 21350 [email protected]

Note

Run the commands below on your local machine, not on your VPS or remote server.

Generate SSH Key

ssh-keygen -f C:\Users\R/.ssh/my_key -t rsa -b 4096

Copy SSH Public Key to Remote Server (Not for Windows)

• Syntax: ssh-copy-id -p PORT -i ~/.ssh/keyname.pub USERNAME@HOSTIP
• Example: ssh-copy-id -p 21350 -i ~/.ssh/id_rsa.pub [email protected]

Copy Public Key to Remote Server (for Windows)

1. Make sure you have a .ssh folder on the remote server.

   • Syntax: ssh -P PORT USERNAME@HOSTIP "mkdir /home/USERNAME/.ssh"
   • Example: ssh -P 21350 [email protected] "mkdir /home/u27653/.ssh"

2. Copy the public key.

   • Syntax: scp -P PORT SSH_PUBLIC_KEY_PATH USERNAME@HOSTIP:/home/USERNAME/.ssh/authorized_keys
   • Example: scp -P 21350 C:\Users\R/.ssh\id_rsa.pub [email protected]:/home/u27653/.ssh/authorized_keys