Our company has a VPN client that we develop and it works on 14.x and it was working on 15.x but ever since I have upgraded to 15.1.1, I do not see any traffic being sent to the TUN interface even though I have it configured as the default route. Can anyone provide guidance or insight into what might have changed around the Network Extensions that could have caused this? Unfortunately I cannot tell if this was happening on 15.0.1. Some things I have tried, to no avail, is disable the firewall and uninstalling/installing of the VPN client. I have no other filters installed that could be interfering. When I try and ping an address I should be able to reach, I get "no route to host" I have also used Wireshark and have observed zero traffic going to the TUN interface.
NOTE, networking works fine when the VPN client is not connected.
@DTS Engineer
Thank you for all your help on this. I am going to close this as answered. In debugging I found that a thread in the extension was actually throwing a BAD_INSTRUCTION error in the OpenSSL lib we were using. After upgrading to a new version of OpenSSL that fixed the BAD_INSTRUCTION everything now works.
Of course the mystery is why does the same client work just fine on 14.x but 15.x it did not?
No matter it seems to be working now and that is all that matters. :-)
Again thank you.