AUTHENTICATION_SUCCESS with no corresponding TICKET_GRANTING_TICKET_CREATED?

[Waldbieser, Carl]

We've just started using CAS v5 and some reports have come in about an issue where a user tries to log in, but just keeps getting redirected to the log in screen in our CAS.
In the audit logs, this appears as 1 or more AUTHENTICATION_SUCCESS events with no corresponding TICKET_GRANTING_TICKET_CREATED events.

We are running CAS v5.0.4 Our deployment has 3 CAS nodes which are behind a proxy and are sharing ticket registry information via the Hazelcast back end. Because we first thought the issue might be related to having multiple nodes fielding requests, we removed 2 of the nodes from the proxy lineup (they still are sharing ticket info, but only one node is fielding the requests).

Has anyone seen this kind of manifestation in their CAS audit logs or understand what it might mean?

Thanks,
Carl Waldbieser
ITS Identity Management
Lafayette College