Lena@??? wrote:
>>> | Many small companies we work with haven's PTR records for
>>> | IP-addresses of mail servers.
>> If you're with a company that doesn't have control over your own rDNS,
>> you should NOT be sending mail out onto the internet IMO, the chances
>> are your ISP provides a relay for you to do this.
>
> No, in such cases the monopolistic (former state) ISP don't provide a relay,
> or the relay is in every blacklist. I repeat: they can't care less.
>
>> We've had very few issues with blocking outright on rDNS
>
> Don't conclude that everybody is like you.
For my own personal mail only, today alone, I have come across two cases
of a legit e-mail system lacking reverse DNS.
One was a friend running a mail server from home, who apparently
couldn't get his ISP to set the RDNS. I've advised him to use a smarthost.
The second is much more typical, and is just a small business which
sends out order emails when you buy something online (cyclestore.co.uk).
I've advised them about the issue and their "web guys" are going to look
at it.
There are still a shed load of legitimate mail systems that don't have
reverse DNS. Block them by all means, but don't be under the impression
that you wont block any wanted mail by doing so.
--
Mike Cardwell - IT Consultant and LAMP developer
Cardwell IT Ltd. (UK Reg'd Company #06920226)
http://cardwellit.com/
