RE: IP NAT outside

Keegan,

I'm not sure the pool is what you want. If this were the ASA or PIX, I would say you should do NAT shifting on both sides.

You can do a mutual NAT shift on just a single router, like this:

ip nat inside source static network 192.168.1.0 10.5.5.0 /24
ip nat outside source static network 192.168.1.0 10.10.10.0 /24

http://www.cisco.com/en/US/products/ps5855/products_configuration_example09186a0080a0ece4.shtml

HTH

-ryan

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of Keegan.Holley_at_sungard.com
Sent: Sunday, July 26, 2009 1:56 PM
To: ccielab_at_groupstudy.com
Subject: IP NAT outside

Can someone answer a quick question about outside NAT please? Cisco's
config guide was once again inadequate. See below:

Cloud1 --- Cloud2

Say you have two clouds both representing companies that have recently
merged. They both use the exact same address space, /24 subnets of
10.1/16. There is routers connecting the two companies together using
/30's in an unused block. The following is configured on the edge router
for cloud1.

hostname cloud1router
Gigabitethernet0/0
description to cloud2
ip address 172.1.2.2 255.255.255.252
ip nat outside

int gigabitethernet0/1
description toCore
ip address 10.1.254.1 255.255.255.252
ip nat inside

ip nat pool merge 11.1.0.1 11.1.255.254
access-list 12 permit 10.1.0.0 0.0.255.255

ip nat outside source list 12 pool merge

So my question is (I think) traffic from cloud1's 10.1/16 will be nat'd to
11.1/16 when sent to cloud2. However, will this cover traffic in the
other direction or would you have to do the same thing on the cloud2
router? Can you just do "ip nat destination ..." on the cloud1 router to
nat in the other direction or does that do something different entirely?

Thanks all,

Keegan

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Received on Sun Jul 26 2009 - 14:41:51 ART