Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

Port mapping?

we have a new email mail box that has 172.16.1.44 natted to 67.x.x.6 for incoming traffic - what i need to happen is have all outbound smtp traffic from 172.16.1.32 to also use 67.x.x.6 - doable?

thanks in advance.

3 REPLIES
Green

Re: Port mapping?

It's "sorta" doable.

The easiest way is to use an internal DNS where the mail server is referenced by its inernal address.

People external to your domain would get the public address, people inside your domain would get the internal address.

You'd need to change the host settings (no real problem if ou're using DHCP) to use the internal DNS as Primary" and an external DNS as secondary.

Good Luck

Scott

New Member

Re: Port mapping?

I thnik a simple NAT would do the job wherein you can natt all ip range to single IP address with overlad as a feature . If u you post [ show run ] that would help .

see / rate if this works

tc

Re: Port mapping?

I didnt know if it was possible, so Ive tested it.

config

int s1/0.23

ip ad 172.16.123.1

ip nat out

int fa0/0

ip nat ins

ip nat inside source list 115 interface Serial1/0.23 overload

ip nat inside source static 172.16.10.5 interface Serial1/0.23

!

access-list 115 permit ip 172.16.35.0 0.0.0.255 any

r1#sh ip nat translations

Pro Inside global Inside local Outside local Outside global

icmp 172.16.123.1:4 172.16.35.5:4 172.16.123.2:4 172.16.123.2:4

--- 172.16.123.1 172.16.10.5 --- ---

It works without a problem

Vlad

95
Views
0
Helpful
3
Replies