[CentOS] sendmail mail relay backscatter issue.

Fri Feb 5 17:51:43 UTC 2010
Simon Billis <simon at houxou.com>

Les Mikesell sent a missive on 2010-02-05:

> On 2/5/2010 9:53 AM, Simon Billis wrote:
> 
>> 
>>>> SNIP
>> 
>>> 
>>> What are you currently using in mailertable to get there?  If you use
>>> [domain] and go to the A record of the same name it might be a problem
>>> - but that might work if you try it.  Where I've used it, the delivery
>>> hosts had their own names that they'd accept in the envelope and the
>>> [IP.address] form would also work.
>> 
>> Currently I have this in the mailertable:
>> domain(1).com                     smtp:smtp2.differentdomain.com
>> domain(2).com                     smtp:smtp2.differentdomain.com
>> ...
>> Domain(n).com                     smtp:smtp2.differentdomain.com
>> 
>> I think that I'm going to have to test this out and see what happens.
> 
> I think it should work to put the smtp2.differentdomain.com in the
> virtusrtable target as long as the destination accepts that as a local
> name - and you'd have to go out of your way to avoid it if it is the
> real hostname or reverse DNS name for the interface.

Thanks for your help Les, I'll test it all I think and see what happens.

S.