Warning Unprotected Private Key File AWS EC2 Error

Warning Unprotected Private Key File AWS EC2 Error #

The reason the "Warning: Unprotected Private Key File" AWS error occurs is because we're trying to SSH into an EC2 instance using a private key that allows read access to other users.

In order to solve the "Warning: Unprotected Private Key File" error in AWS EC2, update the permissions of the private key file to only allow read access from the current user, e.g. chmod 600 ec2-private-key.pem.

Open your terminal in the directory where your private key is located and run the chmod command.

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chmod 600 ec2-private-key.pem

Now try to ssh into the EC2 instance again. For amazon Linux instances the command looks like:

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ssh -i "ec2-private-key.pem" ec2-user@YOUR_EC2_PUBLIC_DNS

If you still get the error, try changing the permissions of the directory that contains the private key. For example, if you store your keys in a directory called ec2, you would do:

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chmod 755 ./ec2

Lastly, make sure you're using the correct ssh command. The username varies between the different amazon machine images (e.g. ubuntu or ec2-user).

To get the correct ssh command for your EC2 instance:

1. In the EC2 console, click on the checkbox next to your instance's name
2. Click on Actions and select Connect
3. Click on the SSH client tab and copy the example ssh command

An easy way to find the username for your AMI is to try to log in as root and read the error message:

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ssh -i "ec2-private-key.pem" root@YOUR_EC2_PUBLIC_DNS

Therefore our SSH command should look like:

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ssh -i "ec2-private-key.pem" ec2-user@YOUR_EC2_PUBLIC_DNS

Further Reading #

• Ping an EC2 instance from your Local Machine
• EC2 Instance Example in AWS CDK - Complete Guide
• EC2 User Data Example in AWS CDK - Complete Guide
• VPC Example in AWS CDK - Complete Guide
• Security Group Example in AWS CDK - Complete Guide
• AWS CDK Tutorial for Beginners - Step-by-Step Guide
• How to use Parameters in AWS CDK