I am migrating an existing dovecot server to a new server. The existing server uses pam_krb5 and works with the plain and gssapi methods. The new server plain/pam_krb5 normal password authentication works. However, the gssapi (tickets) authentication is producing the following error:
=== Begin Error ====
imap-login: Disconnected (no auth attempts in 0 secs): user=<>, rip=192.168.7.61, lip=192.168.7.97, TLS, session=<SPnD7NhWWtrAqAc9>
=== End Error ===
What is causing the "user=<>"? It should be "user=<erik>".
I have been using Thunderbird SSL GSSAPI from a Debian Linux testing/buster XFCE desktop to connect to the existing server for years. When I point it to the new server, I receive the above error.
ssh kerberos gssapi authentication is working fine on the new server.
Most of the doveconf setting between the existing and new servers are the same.
The existing server is 32 bit. The new server is 64 bit running in an LXC container. The existing server dovecot version is the same as the new server.
Notes:
dovecot version: 2.2.31 (65cde28) OS: Debian Linux testing/buster Arch: amd64
Client: Mozilla Thunderbird 52.2.1 (latest)