I can add pem files to my SSH agent very easily using ssh-add, like so:
$ ssh-add /home/jsmith/keys/mytest.pem
But I can't seem to remove them:
$ ssh-add -d /home/jsmith/keys/mytest.pem
Bad key file /home/jsmith/keys/mytest.pem: No such file or directory
The pem file still exists though... I haven't moved or changed it in any way. Why am I having so much trouble removing this pem file from my SSH agent that I just added a moment ago? What's the correct way to do this?
I want to avoid using ssh-add -D (with a capital "D") because that would delete all of the identities from my SSH agent, and I only want to delete the one I've specified.
You have to use the public key for this. So first extract the public key and then remove it from the agent.
ssh-keygen -y -f /home/jsmith/keys/mytest.pem > /home/jsmith/keys/mytest.pub
ssh-add -d /home/jsmith/keys/mytest.pub
The man page mentions the "public" key as well: "if no public key is found at a given path, ssh-add will append .pub and retry".