AWS rookie here. I created a few EC2 instances under my AWS account and reused the same Key Pair for all of them. I believe (IIRC) that I had generated the Key Pair from inside AWS, but that could be wrong.
Over this past weekend I sold my old laptop (after completely wiping the hard disk) and got a new one. I'm just remembering now (:facepalm) that I forgot to copy all my SSH private keys to a flash drive and that I no longer have them.
All I want/need to do is to SSH into my EC2 instances, but to do that I need my SSH keys. I still have AWS console access, and I can log in and view all my EC2 Key Pairs. But I don't see any options for downloading them or updating my EC2 instances with new Key Pairs.
So I ask:
I really don't want to have to tear down my old EC2 instances and re-provision new ones, that will take about a week for me to do (although, arguably, it would serve me right!).
Rebuild shouldnt be nesserary. Id suggest option 2 as its quicker and easier.
1.> Its possible to change/append a new key?
Power off the ec2 instance you want to access ("target").
Create a new ("temporary") instance.
Detach the primary EBS volume from target instance (taking note of its current attachment!).
Attach/mount target volume on temporary instance.
edit appropriate authorized_keys file on the mounted volume.
unmount target volume, and reattach to target ec2 instance (using config you noted when detatching it)
start target instance and login with new key.
delete temporary instance
2.> Yes. Snapshot the instance. Provision a new instance from the snapshot selecting a different key (keypair popup appears when you click launch at end of launch wizard)