In searching the Internet, I find a lot on how to install and configure the anti-spam agents for Exchange Server 2013, but nothing on troubleshooting if they don't appear to be working. I assume this means they generally just work.
As far as I can tell, they stopped working and aren't doing anything. At least, the log files stopped updating we've had a spike in spam. I confess I'm not sure how else to tell for sure if they're doing anything.
The last file modified date in C:\Program Files\Microsoft\Exchange Server\V15\TransportRoles\Logs\FrontEnd\AgentLog is 2 weeks old.
I have uninstalled and reinstalled the antispam agents. I have confirmed they are enabled with a value of TRUE. I have restarted the service and the entire server.
We do not have an Edge server, just the CAS/Mailbox server. It is in a DAG with another server, really just for faster manual failover protection, not at all for load balancing as all external traffic is directed to a single server. Also, I have taken the steps to add the connection filter to the server per http://anewmessagehasarrived.blogspot.com/2013/05/rbl-and-exchange-2013.html, which had been working well until that same date about 2 weeks ago, as seen in the logs.
What are the ways to troubleshoot this when it appears everything is running?
Colin