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New Member

Traffic Shaping

I have two internet Links 1 Serial and 1 ADSL terminating on same router, Need to route SMTP Traffic from serial int and all other traffic from ADSL,

1. Which will be my default route (Serial or ADSL)

2. Adsl is configured for DHCP how will i use !set ip next-hop! Command for non SMTP traffic

3. Fastethernet Int will be configured with ip nat inside command (ADSL int with IP NAT out)

Pls. let me know how to fix this thing up



Re: Traffic Shaping

Since most traffic will be directed out your ADSL inteface, that would be the best choice for the default route.

Next, add a static route for the address of your external mail handler/MTA/POP server, i.e.,

(default route comes form the DHCP info on the ADSL interface)

IP route interface S0/0


IP route

Where "" represents the address of your external mail server (put in your real address) and would be the next hop (your ISP's router).

You can use either syntax: the first sends all traffic with the address of your mail router out to the specified interface (note: the 32 bit mask represents a single address ... your mail server).

The second example send all traffic to the next-hop address. This is the more common syntax.

Ther are some other ways to do it with policy routing and othe lists, but a simple static route should do the trick.

Good Luck


New Member

Re: Traffic Shaping

Thanks Scott,

but my email server is hosted in side of my network.

The catch is, if my email server route mails via ADSL Interface (Dynamic IP), recipient gets as a Spam and cannot reply to those mail, that's why I need to send emails via Serial interface, Serial link is only 128 kbps which is very slow for normal internet browsing

Hope you get my scenario



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