>> I've not been able to find a clear write up on the web of a complete >> working configuration for making a L2TP / IPsec VPN connection to an >> OpenBSD machine with an iPhone.
I found this French link (2012 with the old npppd config, but you may adapt to the new syntax ?) which detail a working config with Iphone : http://blog.brimbelle.org/index.php/2012/02/15/passerelle-vpn-l2tpipsec-pour-smartphone-avec-openbsd/ I hope it can help you. Regards, Bastien