How to add a new SSH key in AWS EC2?

Credits: treewebdesign.weebly

Requirement story:
Assume your colleague doesn’t have the same SSH key which is used to connect the AWS EC2 machine. However, she has her own SSH key in her machine.

She is asking you to help in her situation.

Solution:

Get into EC2 by simple ssh

ssh -i "/path/to/sshkey.pem" ubuntu@ec2-1-1-1-1.us-east-2.compute.amazonaws.com

Once you are in, just check whether key available in the machine:

cat ~/.ssh/authorized_keys

You might see some keys are available in the authorized keys like below:

ssh-rsa ...Iv abc

Regardless the previous key available or not, you just add your colleague’s SSH key in the authorized_keys

Done!

Ask your friend to verify from her machine to AWS EC2 by using her existing SSH key.