Captive Portal Check

A captive portal is a login page in public WLAN networks to restrict Internet access to the approval of certain terms of use. When you see a login page on a public network, your device uses a captive portal check. This allows the device to find out whether you have direct Internet access or not. In Android, for example, your device sends a request to a Google server.

Since mid 2019 I provide a free Captive Portal Check: https://connectivitycheck.sp-codes.de/generate204 You are welcome to use it.

Setup in Android

To change the Captive Portal Check in Android, you need a terminal app or a connection via ADB to a computer.

To use http you can run the following commands with the respective method:

# settings put global captive_portal_use_https 0
# settings put global captive_portal_http_url "http://connectivitycheck.sp-codes.de/generate204"

To use https you can use the following two commands:

# settings put global captive_portal_use_https 1
# settings put global captive_portal_https_url "https://connectivitycheck.sp-codes.de/generate204"

Maybe you have to reboot your phone after updating the settings.

If you are using AFWall+ you need to give access to [1000] Android-System and in some cases [10040] CaptivePortalLogin to make it work.

Setup in Ubuntu

In Ubuntu, the file /etc/NetworkManager/NetworkManager.conf must be changed. Add or change the following lines:

[connectivity]
uri=https://connectivitycheck.sp-codes.de/generate204

Restart the network-manager:

sudo service network-manager restart

Setup in Firefox

Type about:config in the Firefox address bar and search for captivedetect.canonicalURL and network.connectivity-service. Set the URL values to https://connectivitycheck.sp-codes.de/generate204, the domain values to connectivitycheck.sp-codes.de. That's it.

More useful links