mysterious Mail DNS problems...

Hi people,

Ok, so have this VPS I am in charge of. I had basically the domain (or subdomain rather) mail.teen-moods.net setup for my mail services. It was working fine, I was able to connect to get my mail and all that good stuff. But then one day my mail client says that it cannot find the server, and it has been that way ever since. I came here and looked around at similar posts and double checked my DNS records and I'm sure they're fine.

I guess you can referr to this to double check for me, I am totally sure: DNS Crawler Results

Thanks for any help you can provide

you going to have to be more specific on those errors. I was able to connect to both the POP3 and SMTP server just fine. The DNS is kinda screwed, but not for connecting to the servers.

Dave

Well you can connect to them using just the domain teen-moods.net but I orignally was connecting to mail.teen-moods.net ; I know it's not a big deal as far as functionality but I still want to know why this happened for my personal knowledge.

WTF... now it's working... wtf

Anyway, I know I need to setup reverse DNS too, but other than that what do you mean as in my DNS being kinda screwed?

Thanks

The DNS is kinda screwed cause I assume you want mail to work for *@teen-moods.net. However, when a mail server makes a query for MX records like below:

dig teen-moods.net mx

There isn't any. They're hiding under the mail subdomain. So the mail server looking for your MX records falls back to a second type of query:

dig teen-moods.net a

Then it tries to connect to that IP to send the mail. It is generally not recommended to rely on A records to direct people to your mail server. MX is better.

Then there's the issue of your mail server. It thinks it is called "pluto.teen-moods.net". When you finally do setup reverse DNS that little stone is gonna be a real pain since it's easy to overlook. I assume you'll set the IP to point to "mail.teen-moods.net", so your server should announce itself as the same.

It's amusing in a way because Plesk, the admin interface I am using, set up the dns that way by default; Why would it do that if it's not suppose to be like that by standard?

Ok, I deleted that original mx record; and done a new one:
teen-moods.net. MX (10) mail.teen-moods.net.

I checked it out using DNS crawler: Here
That looks better than before right? and I am still able to connect to the mail server so that's a plus too. Imma do a test email also. dnsreport.com said I'm doing ok too! yay!

Time to get that mailserver ident corrected...

Question:

Am I suppose to be able to configure just the mail server to announce itself as mail.teen-moods.net or will I have to set the entire server under the domain of mail.teen-moods.net;

Also, if I have my IP resolving to the address of my mail server rather than just the domain would that cause some problems as far as someone tring to come up with the site and they get that address (pretend they don't just drop the mail subdomain)?

not sure what you're asking with the question, so I'll grab a cement truck and try to hit the answer in the dark.

when I connect to mail.teen-moods.net I want to see this line first thing returned from the server:

220 mail.teen-moods.net ESMTP

When your server sends an email, it better send this line first thing:

HELO|EHLO mail.teen-moods.net

Now tell your server who it is. My suggestion is that anywhere you see that pluto.teen-moods.net you replace it with mail.teen-moods.net. I don't think you can go wrong like that.

Now as for that second question... er... I have no clue what you're talking about. But what I can say is configuring your IP to point to "mail.teen-moods.net" has NO disadvantages. It does nothing but good for you as long as mail.teen-moods.net resolves to that same IP.

My host said that only the sending mailserver(pluto.teen-moods.net), which has a different IP than the recieving mail server(mail.teen-moods.net), needs to have a reverse DNS entry....



Does this seem OK to you?

Let's take a quote from the RDNS post in "Generic DNS references and tips"



If your server announces itself as "pluto", "pluto" resolves to the mail server IP, and the mail server IP resolves to "pluto", then all is gravey. If you want your MX to be "mail" that's fine too.