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reverse DNS issue

I've started having problems sending mail to companies that rely on the PTR records to qualify email. As an example when we send an email to rr.com we get

<<< 554 #5.5.4 Relaying denied. IP name lookup failed for x.x.x.x

in return. The problem is the address it lists is not the address of my mail server, it is the address of my NAT global address on my PIX. Now obviously anything going out through my pix is supposed to look like a NAT'd address and I would image that could include email.

My question is, am I supposed to have a reverse DNS address listed for my global address, or do you think I have some kind of configuration problem with my exchange server?
1 Solution
Hi captony,

> am I supposed to have a reverse DNS address listed for my global address

Yes, being NAT, the outside world thinks that IP address is the direct IP Address of your mail server - it must have a PTR record.

Also, RR is one of those "touchy" ISPs (like AOL) so you may also need to create an SMTP Connector for this one domain -> http://www.amset.info/exchange/smtp-connector.asp

Hope that helps,

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