RADIUS Logins - User no longer can login but others not affected

[dsholm]

After a period of time, it could be hours, days, weeks or months, a user has an issue with logging into the VPN server. NOTHING shows in the server logs and only the client logs show "user authentication failed". tcpdump shows an exchange of packets, RADIUS is never probed, white listing the IP does nothing. The only fix is to restart the service and disrupt services for all others connected.

Logging on the server side is, well if you have dealt with it before, you know what it is.

I cannot get anything useful to troubleshoot this and find the root cause.

Is there a top secret way to enable more detailed server side logging?

Are there tools to troubleshoot this?

Should I just go to v5?