Option A is the best solution but if you are told not to use thenat and global 
command to achieve this then Option B will be used but you still have to 
specify 
thetcp keyword to be correct because the way you have used your access-list  
will affect any other traffic other than telnet...the command set is will be 
like this 

static (inside,outside) tcp 192.168.6.61 23 access-list POLICY-NAT 23
This should be more appropriate


________________________________
From: Mark Senteza <[email protected]>
To: [email protected]
Sent: Wed, December 8, 2010 12:23:37 AM
Subject: [OSL | CCIE_Security] Policy NAT on ASA

Hi again everyone.

A question about Policy NAT on the ASA, and the best option to pick. With 
Policy 
NAT I can use either one of the following options:

What I'm trying to accomplish is that from Router R1, when I telnet to Router 
R4's loopback0 (10.4.4.4) using the R1 loopback0 interface (10.1.1.1), I should 
get the address translated to 192.168.6.61. But if I telnet from any other 
interface, I should get translated to 192.168.6.62

Option A

access-list POLICY-NAT1 extended permit ip host 10.1.1.1 host 10.4.4.4 eq telnet

access-list POLICY-NAT2 extended permit ip any host 10.4.4.4 eq telnet

nat (inside) 1 access-list POLICY-NAT1
global (outside) 1 192.168.6.61

nat (inside) 2 access-list POLICY-NAT2
global (outside) 2 192.168.6.62


Option B

access-list POLICY-NAT1 extended permit ip host 10.1.1.1 host 10.4.4.4

access-list POLICY-NAT2 extended permit ip any host 10.4.4.4

static (inside,outside) 192.168.6.61 access-list POLICY-NAT1

static (inside,outside) 192.168.6.62 access-list POLICY-NAT2


I use Option A because I can be specific with defining the traffic from source 
to host as telnet traffic. With Option B I cannot, and even though when I do 
telnet I get translated to the IP I'm requested to get translated to, I also 
get 
translated to that same IP for all over traffic coming from host 10.1.1.1 to 
host 10.4.4.4. The question only specifies telnet, not any other traffic, so I 
guess I could care or careless about what happens to it just as long as the 
traffic in question gets translated.

If presented with a question like this in the lab, and not told to use one way 
or the other, would option A be the best solution to provide, seeing that its 
as 
specific as can possibly get ?

Mark



      
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