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NAT-URGENT QUESTION- Please HELP

Dear All,

I was reading my NAT Design Paper, because I am going to Implement NAT in My Company.

Now, I want to ask you for only the Process of Static NAT , to allow External Users ? on internet side ? to ? access a specific server inside my LAN.

Which is the things that determine this NAT will Work from External to Internal , or Internal to External ?

Please answer the 3 questions .

1- Is it the Route command that I configured on the router it self , only ?

Or,

2- Is it the Route Command + NAT Table which is configured on the Router it self ?

Because As far as I know, I understood the following:-

To configure the NAT, I have to:-

1- determine which INTERFACE will act as IP NAT OUTSIDE , usually the one which have the IP from the ISP Side.

2- Determine which INTERFACE will act as IP NAT INSIDE , usually the one which have the IP from the Private LAN.

3- Determine the NAT statement , if its STATIC / dynamic /overloading .

4- Determine the Route command .

3- Here is Step 4 , I can make rule to forward every thing from INTERNAL to EXTERNAL or from EXTERNAL to INTERNAL , according to My Design Requirements.

So, from the NAT Command + Route Command , I can make the NAT From External to Internal , or, from Internal to External . is that correct ?

1 REPLY
New Member

Re: NAT-URGENT QUESTION- Please HELP

Dear Mohammed,

Regarding the process of Static NAT, to allow external users(on internet) to access a specific server, use the following command:

ip nat inside source static 192.168.0.4 200.1.1.1

this will specify a one to one Static NAT...

you can even specify ports on both (internal/external) e.g.

ip nat inside source static tcp 192.168.0.4 80 200.1.1.1 80

1) the route is only to make a default route for the router so it knows where to put traffic. e.g. the host on internet is 194.126.2.1 it did reached your router and the nat translation occured later on when your router want to return traffic it should know on which interface to forward it..

so for Nat to works you need to assign 1 the inside interface, 2 the outside interface, 3 the static/dynamic NAT statement, and 4 the route command..

Than, you need all the four steps you mentioned for NAT to work.

Refer to the follwing for NAT order of operation:

http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080133ddd.shtml

Rate if this was helpful,

Wissam

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