Our VPN client rely on __SCNetworkReachability to detect any network change, It works fine normally but recently we have started seeing some issues with customer environment, Reachability goes down frequently. When we looked at logs we have seen host name resolved to two IP address one IPv4 address and other mapped IPv6 IP (i.e 64:ff9b::b96e:55c5). Irrespective of which IP is being used with Reachability class (IPv4 or mapped IPv6) problem is not going away. VPN connects fine and immediately within 1 or 2 secs reachability changes and this put the VPN back to connecting state. Note: This issue is not observed in WIFI or any mobile network doesn't provide mapped IP.

After upgrading to iOS 15, rvictl does not work as expected. It starts the device at rvi0 successfully but within few seconds rvi0 interface is getting closed. Wireshark says interface no more connected. "rvictl -s" prints "Could not get list of devices" after few seconds. Is this a known issue with iOS 15? Any workaround? I've tried on macOS Big Sur, version 11.6