Every couple of weeks without explanation AnyConnect, being run off of our MX400, will stop working and drop all connections also disallowing new connections until the MX is rebooted. Has anyone else had this happen to them before? We have put in several meraki support tickets but they do not have an answer for us. There is no visible indicators that it is not working and we do not know it is in error until users begin to report it. In the logs there is no failure events for AnyConnect.
I had this issue on an MX84, or one that sounds the same where the clients could not authenticate and it would have to be restarted if I wanted to immediately resolve it, otherwise, it seemed to start working again on its own if I let it sit. It was only one of my MX84's that had this issue, but it happens to be the one with the most VPN clients. Touch-wood, the issue went away when I upgraded to 16.7 on that one. What release are you on?