To CAIS Engineers - WAKE UP AND TAKE CARE OF YOUR CUSTOMERS

Tue May 15 23:26:41 UTC 2001

Shawn McMahon wrote:
> On Tue, May 15, 2001 at 02:09:30PM -0500, Brett Frankenberger wrote:
>>
>> My understanding is that we are talking about:
>>
>> (a) Doing a reverse lookup on the IP address, and getting a name.
>> (b) Doing a forward lookup on that name, and making sure you get
>>     the right IP address back.
> 
> No, not the security part of the thread, the mail filter part of the
> thread.  Sorry, should have specified.

... unless the person running the mail server configures it to use the
publicly-visible hostname instead of deriving a hostname from OS
information.  That's how I have my sendmail.cf file configured at home. 
It doesn't seem to have any problems.

Of course, mail server distributions don't come preconfigured this way,
so it will still cause problems for those who are unable/unwilling to
hack their sendmail.cf file.

-- David