dsw4@lucent.com wrote:
> Is there a way for Postfix to resolve hostnames without using DNS. Is
> there a mapping table/file that can be setup for this?

It all depends on what you mean by "without using DNS".

For example, there is the DNS lookup for mail exchanger (MX) records
(or address (A) records) to determine which hostname to send someone's
email to.

This DNS routing can be overridden by entries in the Postfix transport file.

Then there is the DNS lookup of the hostname in order to obtain the IP address(es).

On many types of UNIX/Linux boxes, you can add that info in the /etc/hosts file,
as the previous poster said. Then you have to configure a file in the /etc
directory that says to look at the /etc/hosts file before using DNS (or in lieu of using DNS).

But there is another way to force Postfix to use a particular IP address for a given
hostname, and that is also in the transport file. For example:

host.com smtp:[100.101.102.103]

--
Greg