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New Member

Mapping public IPs to internal hosts


I am not very familiar with WANs and need assistance properly configure for the following situation.

I have a 1601R which is connected to a T1. The ISP has provided a range of public IPs. I would like to map one of them to a mail server inside my private addressed network. Besides adding a NAT statement to translate the outside public IP to the inside private IP of the mail server what if any routing entries do I have to add in order for the 1601 to 'know' how to handle the public IP. Or is a NAT statement enough?


  • Other Network Infrastructure Subjects
New Member

Re: Mapping public IPs to internal hosts

Static NAT is enough, as long as your mail server can reach 1601R with IP protocol.

New Member

Re: Mapping public IPs to internal hosts


you could do one thing. on the ethernet interface you could put 1 public Ip as primary Ip and the private address as secondary. The Server you intend is to be given the public Ip and DG is the ethernet public IP of yr router. other PCs can have the private IP as DG. DG= Def. Gateway



New Member

Re: Mapping public IPs to internal hosts

Hi ,

I know your problem,you can type

"ip nat inside source static tcp 25 25", is public ip , is your private ip.this command is correct ,but I don't

use on my 2621 router,it need higher edition IOS to support possible.

If you can use this command successful,please tell me!

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