Two Networks - One ISP
Posted on 2013-05-28
I hope I can explain this well enough for someone to help me.
I have two networks in my building. They both have a totally separate network infrastructure. Each network has its own firewall (Sonicwall NSA 3500) and each has a different Internet Service Provider.
On one of the networks (call it network-1) I have a fiber primary WAN connection and a Comcast 100mbps business class line on a secondary WAN as a fail-over.
On the second network (call it network-2) I have a fiber primary WAN connection, but no secondary WAN as a fail-over.
What I want to do is use the Comcast 100mbps business class line as a fail-over WAN on both networks. I have 5 static IP addresses with the 100mbps line and I think I can just assign an IP address to the secondary WAN both networks, give them the same gateway address, and that will work.
My problem is, I can’t have connectivity between these two networks. I’m concerned that because the two secondary WAN interfaces have addresses that are on the same segment there will be problems.
Can anyone give me advice on this? Is there a way of doing this safely?