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frostbyte5014
05-02-2011, 10:35 PM
I'm hoping we have a few exchange gurus on TN. I have a customer with exchange server 2010. They are having some issues with sending email. They are getting #550 4.4.7 bouncebacks. They are hosting their dot org email on a dot local server. Their dot org website is hosted externally with a hosting provider. I read somewhere that I needed a PTR record pointing to the server from the hosting provider. I'm not sure exactly what I need. If you can help I would greatly appreciate it.
Frostbyte5014

NorCal Internet
05-03-2011, 08:38 AM
You're not being specific enough about the bounce back message. Typically, the bounce back message is VERY specific about what the issue is. If it's bounced because of a PTR, then it will say so.

Post the entire bounce message for a more accurate suggestion...

But, as for the PTR, that is something your Internet provider, not necessarily your hosting provider (Assuming they are different) would configure.

A PTR is a DNS record that provides name resoution to the IP address. The ISP can either specify a PTR for your IP address, or they may delegate the authority for the IP space to you and your DNS (Unlikely).

Most anti-spam/mail servers don't check that your PTR resolves to the same name as the mail server, but some do. Most simply want the IP to resolve to *SOMETHING*... But, if the ISP is willing to set the PTR to your choice, have them set it to the same name as your mail server... (IE: mail.yourdomain.com)

Again, post the full bounce and we'll be able to ensure that is actually your problem.

Covertrunnin
05-17-2011, 10:05 AM
A bit late to this thread, but I'm going to shoot it out in the dark anyway keep in mind I'm no guru on the subject still a student myself....

A PTR record is not a requirement for your mail system to properly work, it is however part of a growing convention and some sites will refuse your email if you do not have a properly configured PTR. Problem is not every hosting provider allows you to configure PTR records so that may be part of the issue.

Have you configured your A records and MX records? Remember these need to be configured on the public DNS servers not on the internal DNS.

If nothing else check your send/receive connectors.

seedubya
05-17-2011, 01:31 PM
A PTR record is not a requirement for your mail system to properly work, it is however part of a growing convention and some sites will refuse your email if you do not have a properly configured PTR.

Absolutely. A PTR, while not technically required, is ABSOLUTELY necessary if running a mail server nowadays. A pointer record allows receiving servers to both check and REVERSE CHECK your DNS thus ensuring that theres no routing funny business going and thus decreasing the liklihood that you're a spammer.

paristotle
05-17-2011, 03:10 PM
Is it all mail that's bouncing, or is it just mail to certain domains? What's the exact message?

pceinc
05-17-2011, 04:01 PM
Who is the ISP? Connection?

NorCal Internet
05-18-2011, 08:37 AM
The OP hasn't responded in nearly two weeks, so...Not sure any of the comments would be responded to now... But, since other items have been raised here...

A PTR actually is required...Sort of... RFC 1913 states: "Every Internet-reachable host should have a name, and that such names match with a reverse pointer record." Although other RFC's seem to indicate you don't have to have one, specifically when discussing mail servers.

Bottom line is, if you want mail to be delivered reliably in today's world, you need to have a PTR.