Cisco 837 NAT public to private address mapping

[jonesyma]

I would like to know how to program the following on a Cisco 837 ADSL router

Map public address 217.1.2.3 255.255.255.248 provided by my ISP on the ADSL interface to private address 192.168.10.1 255.255.255.0 on the internal ethernet interface. This needs to be done for TCP port 80 and UDP port 5588.
I also have other public to private mappings to do so PAT from the inbuilt web administration is not suitable here.

 

[ChrisAC]

ip nat inside source static tcp 192.168.10.1 80 217.1.2.3 80

Or, if 217.1.2.3 was configured on an interface such as atm0.1 for example then you would use;

ip nat inside source static tcp 192.168.10.1 80 interface atm0.1 80

For the UDP port it's basically the same but using 'udp' and the relevent port number instead of 'tcp'

ip nat inside source static udp 192.168.10.1 5588 interface atm0.1 5588

Don't forget to NAT enable the outside and inside interface as well.

interface Ethernet0
ip nat inside
!
interface ATM0.1 (or what ever you are using)
ip nat outside

Chris.


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Chris A.C, CCNA, CCSA
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