How can I have a single /24 private IP address space that spans two locations across a VPN?
We have a /24: 192.168.100.0/24 that has workstations and servers on it. Servers are .5 through .30, workstations are .50-.254.
- Currently, all this is at a single physical location.
- The servers are all VMWare instances on a single VMWare host.
- We currently use Sonicwall NSA 3600 and similar models
We need to move the servers to a data center (to reclaim the office space, etc), and, for a number of reasons, need to keep the networking as is. (There is extensive configuration at app server and client level giving specific rights to specific IP address, blocking access by IP, and putting different types of users in different IP address blocks.)
When I have done VPN configs in the past, we always had a different subnet at each location. This would break many layers of app setup, so we are looking to avoid it. We need the same subnet (192.168.100.0/24) to span two locations, and for the servers to see the clients properly (e.g. the client IP is represented to the server as it is now, when everything is in one physical location).
I have heard that MPLS and/or L2 servers from a telco may be able to solve for this, but I do not know exactly how. We would prefer to implement this in our own networking gear (to give us flexibility RE location, e.g. not to be completely dependant on telco), but need to understand the options.
Note: - We understand that L2 bridging is not ideal from some perspectives - It is, however, the right thing for this application - We know about using NAT to route a "local" address across to another subnet. No need to explain that. This thread is "how to span a /24 subnet across two location"
a) Can this be done at all?
b) We know that telco has services like this. We want to know: Can we do it in our own gear? (We currently use the Sonicwall NSA 3600, but will migrate off if we need to. What do we need to have, spec wise, in gear to do that?)
c) Suggested "closest options" to this? (e.g. if our dream of VPLS in our own gear is not possible, is there another option between that and telco VPLS that solves in this way?)