Not an actual answer to your question, but it seems that at least some captive portals use TTL 1 to prevent further routing:
https://forum.openwrt.org/t/this-hotel- ... -me/129202
if it applies, here is an example of modifying the TTL on a Mikrotik:
viewtopic.php?t=171544
no idea if it can work.
In your current setup, beside the above there may be other issues due to the double NAT (which is probably unavoidable) and the double DHCP (it all may be irrelevant still it seems to me like an unneeded complication.
If you go for changing the router with a Mikrotik (I would suggest an Ax lite if 4 ports - 3 usable are enough) you could try to set the groove and the router on fixed addresses and set a /30 or /32 between them, and have only the router act as DHCP server for the connected devices.
A few years ago existed a kit called Wifiranger Elite AC which essentially was a groove or metal + a small mikrotik router, they had a "custom" graphical interface that made the connection easier, no idea what was used to make it, not if it was compatible with captive portals, but I bet it was, otherwise the "common" users would have been all over the net whining about the issue, of course in the meantime captive portals may well have evolved becoming more difficult to deal with.
Once (hopefully) you manage to solve the problem, you can try using/mis-using/ab-using a Mikrotik skin to simplify as much as possible the UI for the user.
https://forum.openwrt.org/t/this-hotel- ... -me/129202
if it applies, here is an example of modifying the TTL on a Mikrotik:
viewtopic.php?t=171544
no idea if it can work.
In your current setup, beside the above there may be other issues due to the double NAT (which is probably unavoidable) and the double DHCP (it all may be irrelevant still it seems to me like an unneeded complication.
If you go for changing the router with a Mikrotik (I would suggest an Ax lite if 4 ports - 3 usable are enough) you could try to set the groove and the router on fixed addresses and set a /30 or /32 between them, and have only the router act as DHCP server for the connected devices.
A few years ago existed a kit called Wifiranger Elite AC which essentially was a groove or metal + a small mikrotik router, they had a "custom" graphical interface that made the connection easier, no idea what was used to make it, not if it was compatible with captive portals, but I bet it was, otherwise the "common" users would have been all over the net whining about the issue, of course in the meantime captive portals may well have evolved becoming more difficult to deal with.
Once (hopefully) you manage to solve the problem, you can try using/mis-using/ab-using a Mikrotik skin to simplify as much as possible the UI for the user.
Statistics: Posted by jaclaz — Sun Jan 28, 2024 3:17 pm