It's almost as if the system "believes" that network is not working.

I have also gone back and tested the same VPN/PTP client on iOS/iPadOS 18.0 and it works correctly. So there is obviously something I am missing either in the configuration of the PTP that > 18.0 does not like and is therefore shutting down the network.

Another issue I have noticed and I don't know if it's related but on devices that have 18.0.1 or bigger, my VPN app no longer shows up in the Notifications Settings.

After inspecting the PTP (that I have unfortunately inherited due to a company workforce reduction) I believe I found the issue. It was returning from the startTunnel function before completely setting up the interfaces so we were telling the OS that the VPN was connected when it really wasn't. I suspect we have been getting lucky with all the releases up to now. Once I rewrote the code everything worked.

Using the Feedback Assistant - FB19424182

It appears as if this has been fix in beta6

I'm going to close this for now. I didn't find the reason but I did find a way around it.

/Quinn, Glad you asked. The main reason for my question is because our App is a Custom VPN. When connected to CarPlay we can query the system and get the Primary network interface which is the Cellular interface. But, once our Custom VPN app is running the Primary is now the VPN TUN instead of the Cellular interface, which we need to pass data. The typically way we get around this is to then query for all the Active interfaces, giving preference to Wifi over Cellular. So now we are trying to use the Wifi interface for data when it's being used for CarPlay. I suspect the same issue would occur when the phone is being used as a hotspot but I have not tested that. In any case, I have found a "work around" that works. We now are looking at the WifiNetworkType and if it has a non-zero value do not use it.

We are grabbing the dict from State:/Network/Interface/<ifname>/AirPort and looking at the key WifiNetworkType if that makes sense. [quote='869060022, DTS Engineer, /thread/809596?answerId=869060022#869060022'] But inside your packet tunnel provider NECP should prevent you from accessing your VPN interface, and thus your data should run over WWAN. Is that not working in general? Or not working solely in the CarPlay case? [/quote] The issue is only when connected to CarPlay. The data comes into the PTP and since it's a Custom VPN application we essentially intercept the data to do our Custom VPN "magic" and then we send it out the WWAN afterwards. The issue is knowing what interface the WWAN is to send it out on and to not select the Wifi since it's an ACTIVE interface but being used for CarPlay. The other piece is that if Wifi and Cellular are both ACTIVE we give preference to Wifi. I don't know what more I can say but hope that makes sense. I'll also take a look at your post on networking

Yes, iOS. Is getting to the SCDynamicStore not supposed to be possible on iOS? I inherited this code and it's always been there for me to use so somehow a previous developer added it and I never thought about it

But if theres a better way I'm all ears

Ok I give up. Everything I've tried gives me no indication that the Wifi is being used for something other than network data. I'll just continue to let it fail for now and see if I can come up with another plan in the future. Thanks for the time