...

As an IdP operator you either have bad metadata, or you have a broken SP, and unless you created the metadata, it's not your problem to solve. Only the SP operator knows whether the URL is valid, so you may have to update the metadata or they will have to stop generating requests including the bad URL. The cause of a bad URL is generally a failure to properly configure a web server running the SP to account for local virtualization, load balancing, etc. It could also simply be a failure to update metadata to reflect a change.

Common Log Messages

 org.springframework.webflow.conversation.impl.LockTimeoutException: Unable to acquire conversation lock after 30 seconds

If you see this in the log, usually accompanied by other problems and reports of users unable to login successfully, you are experiencing a problem somewhere between the IdP and some back-end system you have configured for authentication, attribute resolution, or some other kind of remotely accessed functionality. This layer isn't properly timing out fast enough to prevent users from replaying requests, smashing form buttons, etc., and the result is clients stacking up requests that are hung up until the limit on simultaneous requests from one client is reached. Eventually new requests timeout trying to get locks to add new requests to the queue and this starts getting logged.

...