Re: SMTP and MX Records

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From: Attila ($acsokai$_at_nosmap.andrew.cmu.edu)
Date: 10/26/04 

Date: Tue, 26 Oct 2004 08:10:55 -0400

Telnetting to my IP on port 25 as sugested fails. Now that you mentioned
blocking, I just remembered something. I bet its not that the ISP (Verizon)
is blocking port 25, but the DSL modem itself. I do recall now configuring
ports on the DSL modem to make things work before. It is good to know though
that my MX record is resolving at least. That's one step closer.
I will try configuring the DSL modem again and report my findings. Your help
is greatly appreciated.

Attila

"Javier Gomez [SBS MVP]" <javier_gomez@remove.this.engineer.com> wrote in
message news:eGVfhM1uEHA.228@TK2MSFTNGP10.phx.gbl...
> Hi Attila!
>
> With the information given I would have to say that you have one (or
> serveral) of these problems:
>
> 1) Your ISP is blocking port 25 inbound
> 2) Your Router/Firewall or even the SBS server is blocking port 25.
> 3) The Exchange is not answering
>
> How would I test this? Well...
>
> The first thing to do is go to a PC outside your lan (anywhere on the
> internet) and type "telnet x.x.x.x 25" (where x.x.x.x is the PUBLIC IP of
> your server). If this works-> Could you post your domain, so I can check
> the dns records? (you can send it to me by email if you don't feel
> confortable posting it).
>
> Additional testing...
>
> 1) On the server run "telnet sbs-server.domainname.local 25" and see if
> you get a response. You can rule out problem #3
> 2) Connect a laptop parallel to the external nic of the SBS server. Then
> from the laptop "telnet x.x.x.x 25" (where x.x.x.x is the IP of the
> external NIC, not necesarily a public IP). If you have a router do the
> same, but parallel to the router. Do you get a response on both cases? If
> so, you can rule out #2
> 3) I'm not sure how to definitely test if your ISP is blocking port 25,
> but if your ISP is large enough... do a google search or post it here
> (most people knows).
>
> Cheers,
>
> --
> Javier [SBS MVP]
> www.sbsmvps.com/javier
> << SBS ROCKS !!! >>
>
> "attila" <gcsokai-nospam@yahoo.com> wrote in message
> news:%23uO9JYxuEHA.3972@TK2MSFTNGP15.phx.gbl...
>> Javier,
>>
>> Here is what I got from the Email Tester at www.dnsstuff.com Basically it
>> find my domainname correctly and then is tells me that
>> "mail.mydomain-name.com. - my correct IP address [Could not connect:
>> Could not connect to mail server (timed out).]"
>> Any ideas, Results are below:
>>
>> Getting MX record for mydomain-name.com... Got it!
>> Host: mail.mydomain-name.com Preference: 5 IP(s): my correct IP address
>> Step 1: Try connecting to the following mailserver:
>> mail.mydomain-name.com. - my correct IP address
>> Step 2: If still unsuccessful, queue the E-mail for later delivery.
>> ===========================================================T
>> rying to connect to all mailservers:
>>
>> mail.mydomain-name.com. - my correct IP address [Could not connect:
>> Could not connect to mail server (timed out).]
>>
>>
>>
>> "Javier Gomez [SBS MVP]" <javier_gomez@remove.this.engineer.com> wrote in
>> message news:O%23dAj9wuEHA.1988@TK2MSFTNGP12.phx.gbl...
>>>> What should my E-Mail domain be when the CEICW prompts for it?
>>>
>>> mydomain.com
>>>
>>>> The MS help on this page of the CEICW says that the e-mail
>>>> domain name should match the mail exchanger (MX) resource record
>>>> maintained
>>>> at your ISP. This must be a registered Internet domain name.
>>>
>>> I know that statement is confusing... but before this it states that you
>>> should use the internet-registered domain name.
>>>
>>>> So should my email domain name specified in the CWICW be
>>>> mail.mydomain.com or just mydomain.com?
>>>
>>> mydomain.com
>>>
>>>> Also, is there a propagation delay of minutes, hours or days before I
>>>> should expect to be able to receive mail with this new setup?
>>>> Port 25 is opened on the router by UPnP of CEICW.
>>>
>>> That depends on the settings your DNS provider... but if you are not
>>> changing nameservers this should be almost immediate (i.e. from
>>> instantaneous to no more than a couple of minutes). You can check the if
>>> the mx record is updated on www.dnsstuff.com.
>>>
>>> --
>>> Javier [SBS MVP]
>>> www.sbsmvps.com/javier
>>> << SBS ROCKS !!! >>
>>>
>>
>>
>
>

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