This version of GitHub Enterprise Server was discontinued on 2024-07-09. No patch releases will be made, even for critical security issues. For better performance, improved security, and new features, upgrade to the latest version of GitHub Enterprise Server. For help with the upgrade, contact GitHub Enterprise support.

Error: Agent admitted failure to sign

In rare circumstances, connecting to GitHub Enterprise Server via SSH on Linux produces the error "Agent admitted failure to sign using the key". Follow these steps to resolve the problem.

When trying to SSH into your GitHub Enterprise Server instance on a Linux computer, you may see the following message in your terminal:

$ ssh -vT git@HOSTNAME
> ...
> Agent admitted failure to sign using the key.
> debug1: No more authentication methods to try.
> Permission denied (publickey).

For more details, see this issue report on Canonical Launchpad.

Resolution

You should be able to fix this error by loading your keys into your SSH agent with ssh-add:

# start the ssh-agent in the background
$ eval "$(ssh-agent -s)"
> Agent pid 59566
$ ssh-add
> Enter passphrase for /home/YOU/.ssh/id_rsa: [tippy tap]
> Identity added: /home/YOU/.ssh/id_rsa (/home/YOU/.ssh/id_rsa)

If your key does not have the default filename (/.ssh/id_rsa), you'll have to pass that path to ssh-add:

# start the ssh-agent in the background
$ eval "$(ssh-agent -s)"
> Agent pid 59566
$ ssh-add ~/.ssh/my_other_key
> Enter passphrase for /home/YOU/.ssh/my_other_key: [tappity tap tap]
> Identity added: /home/YOU/.ssh/my_other_key (/home/YOU/.ssh/my_other_key)