"UNPROTECTED PRIVATE KEY FILE!" Error using SSH into Amazon EC2 Instance (AWS)

Question

This is probably a stupidly simple question to some :)

I've created a new linux instance on Amazon EC2, and as part of that downloaded the .pem file to allow me to SSH in.

When I tried to ssh with:

ssh -i myfile.pem <public dns> 

I got:

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @         WARNING: UNPROTECTED PRIVATE KEY FILE!          @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ Permissions 0644 for 'amazonec2.pem' are too open. It is recommended that your private key files are NOT accessible by others. This private key will be ignored. bad permissions: ignore key: amazonec2.pem Permission denied (publickey). 

Following this post I tried to chmod +600 the pem file, but now when I ssh I just get:

Permission denied (publickey). 

What school-boy error am I making here? The .pem file is in my home folder (in osx). It's permissions look like this:

-rw-------@   1 mattroberts  staff    1696 19 Nov 11:20 amazonec2.pem 

Answer 1

The problem is having wrong mod on the file.

Easily solved by executing -

chmod 400 mykey.pem

Taken from Amazon's instructions -

Your key file must not be publicly viewable for SSH to work. Use this command if needed: chmod 400 mykey.pem

400 protects it by making it read only and only for the owner.

Answer 2

You are likely using the wrong username to login, because—

• Most Ubuntu images have a user ubuntu
• Amazon's AMI is ec2-user
• Most Debian images have either root or admin

To login, you need to adjust your ssh command:

ssh -l USERNAME_HERE -i .ssh/yourkey.pem public-ec2-host