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Messages Being Returned, No Reverse DNS

Z

zboyblue

Guest
I am getting messages returned when sent from at least one of the domains on my server.

If anyone could PLEASE help me with this I would greatly appreciate it.

Thanks!

Craig

Here are the messages that I received ...

<[email protected]>:
64.224.219.122 failed after I sent the message.
Remote host said: 554 5.7.1 The server sending your mail [199.72.171.10] does not have a reverse DNS entry. Connection Rejected. Please contact your Dial-Up/DSL/Network ISP Provider. Default Reject!

<[email protected]>:
205.188.158.25 failed after I sent the message.
Remote host said: 421-: (DNS:NR) http://postmaster.info.aol.com/errors/421dnsnr.html
421 SERVICE NOT AVAILABLE
I'm not going to try again; this message has been in the queue too long.

<[email protected]>:
205.188.156.185 failed after I sent the message.
Remote host said: 421-: (DNS:NR) http://postmaster.info.aol.com/errors/421dnsnr.html
421 SERVICE NOT AVAILABLE
I'm not going to try again; this message has been in the queue too long.

<[email protected]>:
64.12.137.89 failed after I sent the message.
Remote host said: 421-: (DNS:NR) http://postmaster.info.aol.com/errors/421dnsnr.html
421 SERVICE NOT AVAILABLE
I'm not going to try again; this message has been in the queue too long.
 
Hi Craig,

Don't worry too much. This is easy to fix.

Under normal circumstances. reverse DNS entries need to be added by your "ISP" (effectively whoever actually "owns" your IP addresses). This might be your co-lo company (or the company you lease/rent your server from), or their upstream provider.

So contact whoever you pay for your machine and IPs, and ask them to set up reverse DNS entries for your IP addresses.

This should only take a short while to set up, and all will then be well.

I'm surprised that reverse dns entries aren't added as standard, but they weren't by the company we col-lo with either -- I had to ask -- so maybe there's a good reason for not doing it by default.

Faris.
 
But I dont understand, it has been working for 2 years with no problems. I just upgraded to 7.5 Reloaded about a month ago, that is really the only thing that has changed.

Let me know if this changes anything, I just dont understand how it could work for 2 years and then stop all of a sudden.

Thanks for any help.

Craig
 
Oh. I see. that is confusing.

Can you check to see that you have a PTR record for your primary domain?

Could the upgrade to 7.5 somehow have changes what your system considers to be the primary domain? Hmm.. No, I don't see how that could happen.

I'm afraid I don't know enought about this.

But look here:

www.dnsstuff.com

In the second (i.e. middle) column, the second item down is reverse dns lookup.

Enter the IP address that your server uses to send email from. Note: If you have more than one IP address, the one your system uses to communicate with the outside world is usually the first IP address on the highest numbered ethernet port.

So if you have eth0 = IP1
and eth0:1 =IP2 your system will usually send from IP1

But if you have eth0 = IP1
and eth1=IP2
and even eth1:1 = IP3
then it will send from IP2

At least I think this is the case!

Anyway, maybe just send yourself an email and check the IP address it says it is sending from :)

So, when you enter the IP address in the page and check it, if your ISP has reverse DNS, the Answer section will look like this:

Answer:
xxx.xxx.xxx.xxx PTR record: somewhere.somewhere.tld. [TTL 18000s] [A=xxx.xxx.xxx.xxx]

Alternatively, if there is no rDNS, it will look like this:

Answer:
No PTR records exist for xxx.xxx.xxx.xxx. [Neg TTL=86400 seconds]


Faris.
 
Thanks so much for trying to help me.

I have a pointer record for each of my domains for the IP it is on. I have 3 IP's on my machine and domains are on different IP's.

I am not sure what to do from here, I wonder if it was just a problem with AOL's servers that day or something?

Any other ideas for troubleshooting this would be greatly appreciated.

Craig
 
A reverse lookup is required by AOL and some others or they will not deliver mail from your server. I had this problem with AOL 6 months ago when I did not have a reverse lookup. After a few weeks AOL started deliving my mail again. Now they have stopped for the same reason. I have requested Hostcentric, my host to do this for me more than a week ago and am still waiting for it to be done. Unfortunately whoever is responsible for the network must do this. Even though I do my own dns I must depend on Hostcentric for this function.
 
I have emailed my T1 provider to see if they can do anything. I will post back if they solve the problem.

Craig
 
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