Accessing a Linux AWS EC2 instance from a Windows environment requires a secure SSH connection. When an EC2 instance is created, AWS provides a PEM private key for authentication, and a corresponding public key is automatically installed on the instance. This key-based approach ensures a protected channel for managing and controlling resources on the remote server.
Because Windows does not include a native SSH client, a third-party tool such as PuTTY is often used. PuTTY is a widely adopted SSH client that relies on the PPK format for key files, requiring a simple conversion from the PEM file provided by AWS.
Before initiating a connection, the security group associated with the EC2 instance must allow SSH traffic from the appropriate IP address. This configuration confirms that all incoming network traffic is correctly authorized. Once set, administrators can securely manage Linux instances from a Windows host.
Steps to SSH to Linux AWS EC2 instance using PuTTY:
- Confirm the security group for your EC2 instance allows SSH traffic, or use a VPN or proxy server if necessary.
Related: How to create SOCKS proxy on Windows
- Convert your PEM private key file to PPK (PuTTY Private Key) format.
- Download PuTTY from the official website.
https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html
- Launch PuTTY.
- Enter the Host Name or IP Address of your ec2 instance.
- Go to Connection → SSH → Auth from the sidebar menu.
- Click on the Browse button to look for your PuTTY Private Key.
- Select your PuTTY Private Key from the stored location and click on the Open button.
- Click on the Open button to start the connection.
- Click Yes if a security alert pops up as this is your first connection to the server and the server's key fingerprint is not in your PuTTY's cache.
- Enter the username that you want to connect as and press enter.
- Enter the passphrase for the key if a passphrase protects your key.
- You should now be logged in using the public key authentication to the system.
Mohd Shakir Zakaria is a cloud architect with deep roots in software development and open-source advocacy. Certified in AWS, Red Hat, VMware, ITIL, and Linux, he specializes in designing and managing robust cloud and on-premises infrastructures.
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