Our LAN segment consisted of two public IP subnets. The second was added because more IP addresses were needed.
We have since implemeted NAT (with overload) on our perimeter router, and are in the process of migrating all hosts to a private subnet. The router's internal interface has secondary addresses for the second public subnet and the private subnet.
The problem I have is I need to implement a PIX between the router and the network BEFORE all the file servers can be migrated to use only the private IP address.
Can I temporarily run both the private subnet and one of the public subnets on the LAN while using the other subnet on the PIX outside interface for NAT?
Would this require another router to be placed between the PIX and the internal network?