so, now we have setup like this:
LAN1 <--> MT1 <--> internet <--> MT2 <--> LAN2
both LAN's use the same subnet of ip's (with nat to internet) and there are pptp/eoip/bridge link connecting them.
plan is to get one more internet connection for each of mt's and use those as a backup links.
it is no problem to create such setup with working internet.. but about vpn.. well, i'm confused there.
ok, as i understand, there should be no problem with pptp server side.. just open the appropriate ports/protocols for appropriate ip's and do not specify the caller id..
but what to do when pptp server's primary connection dies.. how do i get the client to automatically connect to the server's backup link ip ? or should i set up 2 simultaneous connections and somehow mangle with bridges and stp ?