@RockPaper the router serves mostly like a dns relay. Most do. Between any vendor. if you want true dns resolution, you will need to host an interal dns server. Adgaurd home and or pihole will...

@Aviv_Malka That must be an old controller version... I do not see it in my OC200 device list.

@MDRAJU Can you confirm your VLAN Settings on the wifi section are correctly entered? What model router/switch are you using?

@TechBill https://community.tp-link.com/en/business/forum/topic/622852?replyId=1254860

@IanCC To play it safe, I would self-host. The OC300 does say 15k Clients, but it doesn't mention guest portals.

@TechBill Yup thats it!