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amoos

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DNS issue

ok I had my ISP create a reverse lookup and ptr for my new exchange server because I was unable to send mail to certain domains now that I had them add the external ip that my exchange server dishing out.  My ISP hosts my DNS. Do I have to point that new record to my internal ip of my server?? Or is it just for the ISP's reverse lookup???  Help I am confused
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Tom-J-Lael
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this question is worded kind of weird and doesn't make much sense...i'll try my best

the IP's you'd use would be routable IP's but you get the picture...


an A record should point the host name of your exchange server to IP address

exchangehost.domain.com points to 192.168.0.1


PTR record points IP address to A record

192.168.0.1 should point to exchangehost.domain.com

and your MX record  for your domain.com should point to the A record that points to your Exchange server

You should also set your exchange server's Helo/Ehlo to match your A record

Open Exchange System Manager
Drill down to your Default SMTP Server
Right click and select properties
click the delivery tab
click Advanced
and in the full-qualified domain name section type in the complete A record that points to your Exchange server:

exchangehost.domain.com

restart SMTP service just to be safe

also check your IP Address against the Spam Database Lookup tool on www.dnsstuff.com to see if you're blacklisted anywhere
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amoos

ASKER

are you refering to the SMTP banner??
I think? I haven't heard it referred to as that, but that makes more sense
basically..your SMTP banner should not be an IP address..it should be a FQDN
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ASKER

I absolutely agree.  And it is. It is myservername.mydomain.org

I am sorry I have left things out

My DNS is completely hosted by my ISP

I have an internal of .local
I have an external of .org

All the external ip's that were given to me by my ISP are forwarded to my to my exchange server

I have one forward lookup zone for .local and it has forwarders in it to go to it ISP's DNS servers

Mail was flowing in fine but I noticed that my users were not able to send mail to certain domains I.e. Comcast, aol

So I had the add a host record for external ip that my server was giving out and create a ptr for my server


So my question is that new host they created that is for reverse lookup, do I need to point that to my server through my firewall????
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ASKER

if I am confusing you please let me know
Whatever PTR record they created has to match an existing A record that points to that very same IP address. It all has to resolve exactly.

It's best if that A record points to the IP address the email is coming from as well.

Check DNSStuff.com and make sure you're not blacklisted...if you're not...that's good! You'll still have to manually request to be unblocked by AOL and Comcast...a pain..but that's been my experience
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ASKER

I am not on any blacklists.  This I know for a fact. I check them every other day.  My problem with mail not going to certain domains was that some of the domains were doing a reverse lookup on me and there was nothing there for them to check.  Now there is. So that was resolved.  Now I can send to those domains.  

My ISP has 10 mail.mydomain.org as the mx record.  Does my SMTP banner have to match this????
Your SMTP banner just needs to match the A record that your MX record points to...not the priority
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ASKER

so if mail.mydomain.org is the mx then my SMTP banner should be that???
ASKER CERTIFIED SOLUTION
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Tom-J-Lael
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ASKER

cool.  Cheers