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Static NAT for whole subnets

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Oct 22, 2001
431
US
All,
We're looking at implementing a substantial number of 1-to-1 static NATs on our ASA 5510, a range of public IPs NATed back to a range of privately-addressed hosts. The catch is, we cannot use dynamic pools because 50.50.1.1 has to translate to 10.10.1.1, 50.50.1.2 <-> 10.10.1.2, etc, every time, and there's enough IPs involved to make one config line per IP impractical. I've looked around both in this forum and elsewhere on the internet and haven't found a solid solution; is anyone familiar with the cabability (and if so, syntax) of the ASA to do a "subnet-to-subnet" static NAT?

CompTIA: A+ (WfW 3.11), Network+
Microsoft: MCSE+I (NT4)
Novell: CNE (4.11, 5.0)
Citrix: CCA (Metaframe 1.0)
Cisco: CCNA (current)
Working on MS 70-642 then CCNP...
 
What version of ASA? I beleive this is possible with the newest code that uses new and confusing nat commands. :)
 
I found the solution, it's obvious in retrospect. A 'normal' one-to-one static NAT config line is as follows:

static (inside,outside) 197.92.76.1 10.0.0.1 netmask 255.255.255.255

Result is:
197.92.76.1 <--> 10.0.0.1

But if you HAVE to specify the netmask, then what happens when you adjust the netmask?

static (inside,outside) 197.92.76.0 10.0.0.0 netmask 255.255.255.0

This one-to-one's the entire /24:
197.92.76.0 <--> 10.0.0.0
197.92.76.1 <--> 10.0.0.1
197.92.76.2 <--> 10.0.0.2
197.92.76.3 <--> 10.0.0.3
...
197.92.76.255 <--> 10.0.0.255

CompTIA: A+ (WfW 3.11), Network+
Microsoft: MCSE+I (NT4)
Novell: CNE (4.11, 5.0)
Citrix: CCA (Metaframe 1.0)
Cisco: CCNA (current)
Working on MS 70-642 then CCNP...
 
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