2 ms·
> I don't have an easy solution for this one. Building your own box and doing the co-lo thing is just far too annoying for a lot of people. VPS on Vultr: $2.50
by wahern 8y ago
> I don't have an easy solution for this one. Building your own box and doing the co-lo thing is just far too annoying for a lot of people.
VPS on Vultr: $2.50/month.
Additional IP address on Vultr: $2.00/month.
Forwarding additional routable IP address to dynamically addressed server with a 1-line IPSec config on each end: $0.00.
You can of course use OpenVPN or Wireguard instead of IPsec, but it's a little more complicated as you need to forward the IP across a tunnel with two known end points[1], which you obviously don't yet have. To get the two known end points you'd need to establish a privately addressed[2] VPN plus configure explicit routes to forward the fixed IP over the VPN. With IPSec the initiator (i.e. the box lacking a fixed external address) can dynamically establish a tunnel for the additional IP directly, without the indirection.
It's one case (and perhaps the only typical case) where IPSec's flow-based rather than route-based configuration policies are clearly beneficial. Otherwise IPSec's flow-based policies are an endless source of confusion as most people and most systems' network stacks are primarily route based.
[1] Because they use routed-based configuration policies which require, a priori, having a known end point to route to, as opposed to IPSec's flow-based policies which can capture a packet and forward to whatever peer (and whatever IP address) has been most recently authorized (by IKE) to receive it.
[2] Unless you have a whole routable subnet to spare, in which case you wouldn't even be facing the hosting dilemma.