I currently have a pix (6.3) with the outside interface configured as part of a /27 bit public ip space. We are running out of addresses and need to purchase another range. Can I make this work using the existing pix and without tampering with the existing range in use? Basically, can I route a new address space to my existing pix and set up statics for that space even though the interface is assigned an ip address on a different range?
YES, it can be done rather easily.
Example: your outside interface is
126.96.36.199/27. Now you want to add another
188.8.131.52/24 to your outside interface.
Is that correct?
The technique is to use routing IP NAT Pool.
In this example, you will add a static route
on the upstream router like this:
ip route 184.108.40.206 255.255.255.0 220.127.116.11
Now you can do static NAT on the pix as
static (i,o) 18.104.22.168 192.168.1.0 netmask 255.255.255.0