@jmursyd Yes, it is possible, but the network topology should better be like AP CPE))))Client CPE----AP CPE))))((((Client CPE. The connection will be more stable.

@cmcouwenb I am also currently running Controller V5.8 and have tried changing the port to 443 without similar problems. Have you checked to see if there are any devices on your network or server...

@ThorstenStr If your local subnet is different from the default LAN of ER8411, it may cause the issue, so suggest you change the ER8411 LAN subnet to the one that you used currently. Hope this can...

@HwaHin Does it affect actual use? Does the same problem exist when CPE working in other modes?

@words Can this help you: How to limit specific IP to access to internal server

@kornellz101 I think you need to set URL Filtering on your router, not on the switch. As I known, switches generally only work on Layer 2 or Layer 3.