Does VPN work on Android 13?

Why is L2TP VPN not working on Android 13?

This guide will show how to get L2TP/IPSec VPN working on the latest Android system updates (Nougat 7.1 and Oreo 8.1). This should work with any rooted Android that supports root access. In general, these are devices running on the newest hardware from Huawei, LG, OnePlus, Essential and others. You can also follow this guide using a device running Android 8.1 Oreo by updating to AOKP Beta 8. I think this should work on most other recent Samsung devices as well, but I can't be sure, so best just to try it on your own device. Also, some other devices will not use this guide directly, but you will need to follow the guide and then update the software on a device that uses stock Nougat or earlier. I did not test this on many Nexus devices, but it looks like I don't need to use an app for the L2TP VPN to work properly, at least on newer devices without a custom ROM. More recent Nexus devices may require something like Termux.

I've tried many different L2TP VPN guides to fix the issue, but none of them were successful. The issues seem to be related to "security patches" required for Nougat/Oreo. Google only allows OEMs to release security patches during maintenance windows. For example, the Galaxy S6 is released with patches after it is turned off. These patches are only allowed to be downloaded to devices when the device is ON! The Galaxy S7 and S7 Edge and a bunch of other new phones also require special firmware (that includes a kernel patch) for the Galaxy S7 and S7 Edge in order to load the latest Android updates. This firmware was pushed to devices as part of an "unboxing experience" for these new phones. That process is not compatible with rooting. It also can't be loaded to a device using an app called Magisk because Magisk causes device to hang when booting after upgrading to Oreo. This process requires device to be powered off (turn off). For this reason, there isn't a simple way to install Oreo.