You can configure how the Key Agent presents RSA signatures in response to the Agent Identities Request. Whenis enabled (the default), the agent sends only ssh-rsa and x509v3-sign-rsa signatures. When this option is unchecked the agent also sends SHA256 signatures (x509v3-rsa2048-sha256 and firstname.lastname@example.org).
To enable support for SHA256 Signatures
From the Key Agentmenu, uncheck .
NOTE:Agent forwarding to some servers may not be supported when this option is unchecked because of the length of the reply to the list request.