Ssh key persists even after I delete the private key from ~/.ssh — why

Make sure you have a corresponding id_rsa.pub or id_dsa.pub in your ~/.ssh directory.

When I had an id_rsa but not a corresponding id_rsa.pub, Mac OS X kept popping up the dialog and remember passowrd in my keychain did nothing.

cd ~/.ssh
ssh-keygen -y -f id_rsa > id_rsa.pub

generated the appropriate public key file for me.

If you already had your public file there (rename it to another name) and generate the public key again using the above command, you'll notice that the generated and the old one are not equal. Somehow the older versions of Mac OS X generated a public key that Lion does not like anymore, generating it again fixes that.

For the curious, the key is exactly the same, the part that changes is that there is no "comments" section after the key on the file any longer.

I had this same problem. However, when a generated a new password-less private key, using the following command:

ssh-keygen -b 1024 -t rsa -f id_rsa -P ""

I no longer saw the password prompt.

Additionally, ssh-add failed to add the old key, but added the new one as expected.

I generated the old key on Leopard in 2009, using what ever version of OpenSSL I had grabbed, built and installed back then (that Mac died, so I can't log in and check what I was running). Something about that key was incompatible with Lion's native SSL libraries.

I backed up my old key, so if anyone wants to suggest some checks, to identify the key's specific properties, let me what to check and I'll report back.

Another clue - I noticed that my old id_rsa.pub file had extended attributes. i.e. it's permissions flags looked like this r--------@ instead of r--------

xattr -l id_rsa.pub.old

returned:

com.macromates.caret: {
    column = 0;
    line = 1;
}

cruft left over from TextMate. I don't know if removing it would have fixed the issue without my having to replace the key. I think it's unlikely.

In case you (future reader) are seeing the same thing, you can remove the extended attribute as follows:

 xattr -d com.macromates.caret id_rsa.pub.old

You can stop TextMate from adding them by first exiting TextMate and then issuing this command:

defaults write com.macromates.textmate OakDocumentDisableFSMetaData 1