Captive portal using DHCP option 114 not working on Android/iOS

[praveenvaniamkulam]

This is regarding the captive portal example code given in
https://github.com/espressif/esp-idf/tr ... ive_portal

Example works well for the first approach using "funnelling" of DNS. Client opens the captive webpage, once connected to AP.

I tried using the second approach i.e. by DHCP option 114. CONFIG_ESP_ENABLE_DHCP_CAPTIVEPORTAL is enabled. To ensure that DNS re-direct does not happen, DNS server is disabled in the code.

It is expected, once connected to AP, the client prompt to captive page from the URI provided in DHCP offer.

But this didn't happen. I tried with both Android and iOS devices but this approach was not working. I could manually access the webpage from browser.

Is anything overlooked?