Any existing scenario for VPN infrastructure with OSPF configuration? howto's, tips and quick hints are most welcome

do u have the script that do a failover?You can write a scrit that checks your primary pptp link, if it fails - enable backup link.
You can write a scrit that checks your primary pptp link, if it fails - enable backup link.
/ip route add gateway=192.168.1.1 check-gateway=ping
/ip route add gateway=192.168.2.1 distance=2
i have seen no issues with vpn it is my favorit part of the os