Sending email to my local server

[Rick Stevens]

On 05/20/2014 06:45 AM, Timothy Murphy issued this missive:
> Rick Stevens wrote:
>
>>> I'm trying to send email from my Fedora-20/KDE laptop "rose"
>>> to my CentOS-6.5 local home server "grover"
>>> (in order to run a SpamAssassin test),
>>> but I am finding this surprisingly difficult.
>
>> Are you certain that grover is running an MTA and that it's listening
>> to anything other than 127.0.0.1? Easiest way to find out:
>>
>> # netstat -lpnt | grep :25
>>
>> If you only see something like:
>>
>> tcp        0      0 127.0.0.1:25 ...
>>
>> then it's running, but won't accept incoming mail from the outside
>> world. You'll need to bugger the config to make it listen to an
>> additional IP. How you do that depends on if it's sendmail or postfix.
>
> Thanks very much for your help.
> The above command gives
>
>    [root at grover mail]# netstat -lpnt | grep :25
>    tcp  0  0  0.0.0.0:25  0.0.0.0:*  LISTEN  27501/sendmail
>
> I'm using sendmail on this server,
> and I previously modified sendmail.mc as follows:
>
>    dnl DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl
>    DAEMON_OPTIONS(`Port=smtp,Name=MTA')dnl
>
> (afterwards running /etc/mail/make and re-starting the sendmail service).
>
> I take it from the result of your command that sendmail on the server
> is only listening to localhost?

No, you did it right. The "0.0.0.0:25" indicates that sendmail is
listening on all IPs on the machine.

> I should say that this is not a vital issue for me.
> I was just trying to send the gtube spam test string to the server
> to test SpamAssassin (which is working, but not as well as I would like).
> If I send the message to my email address, it goes to my ISP's server,
> which not surprisingly rejects it.
>
> I realise now I could, and probably should, have sent the email
> directly from the server rather than from my laptop.
> When I do this I see that it is rejected with an SA score of 997.1
> which seems like overkill!
> This worked when sent (with "mail") to tim , tim at localhost ,
> tim at localhost.localdomain and tim at grover.gayleard.com ,
> but not when sent to tim at grover or tim at gayleard.com .

Ok, so now you have to look at your resolv.conf file and see what the
completion for incomplete names is (e.g. what do the parameters for
"domain" and "search" define) to see how the "sending" host will be
identified.

I see your MX record for gayleard.com shows "mail.gayleard.com" as the
mail server, therefore any mail will try to go to that machine for
delivery. I also see there is no reverse DNS for the IP address assigned
to mail.gayleard.com. That can cause issues downstream (many mail
servers won't accept mail if the reverse DNS for the connecting machine
doesn't work as that's a classic spammer mechanism).
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- Rick Stevens, Systems Engineer, AllDigital    ricks at alldigital.com -
- AIM/Skype: therps2        ICQ: 22643734            Yahoo: origrps2 -
-                                                                    -
-          Consciousness: that annoying time between naps.           -
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