Pix 515 add range of public ips to internal network

Unanswered Question
Nov 17th, 2008


We have a new range of public ips and need to add them to a new internal interface (not the outside one). Therefore I need to find out how to pass these IPs through the outside interface on to the new internal interface net2 without NAT.

I've tried lots of different configs in the office test environment but its not working. In this example lets say I need to assign to a host on net 2. Then access this host on port 80 from the outside interface.

The test rig is as follows.

outside -

inside -

net2 - no ip default gateway router


Pix 515 7.0.(2)

The test machine in net2 is

The pix can't ping that host and we can't get any packets to or from it.

Also noticed arp is not showing on any interface of pix after a ping.

# Log extract

Built inbound TCP connection 1848027 for outside: ( to net2: (

Routing failed to locate next hop for TCP from outside: to net2:

Can anyone tell me what I need to do to the configuration to get this working or point me to a suitable example. I've yet to find one on the cisco website or anywhere else.

Any help much appreciated.


I have this problem too.
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Jon Marshall Mon, 11/17/2008 - 05:37


Are you trying to host part of the network on a different interface than the outside one ? If so i suspect the reason you can't find an example is because you can't do this.

When you say a new range do you just mean more IP's from the same /24 subnet ?. What you could do is break down the /24 subnet using VLSM and then you wouldn't have overlapping addresses on the 2 interfaces.

Apologies if i have misunderstood what you are trying to do.



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