problems receiving e-mail to my server redux

[Cowles, Steve]

Ed McCorduck wrote:
> 
> Hi Steve,
> 
> Here's what my ISP told me about any blocking of smtp connections:
> 
>> Road Runner does not block any significant ports on your
>> connection. The Road Runner service only blocks ports 137-139
>> inclusive for the security of your system. These blocked
>> ports will not affect connectivity

That's good to know. Lets just hope the RoadRunners left hand knows what the
right hand has implemented. :-)

With the above in mind, there are 3 basic tasks that you will need to
implement at your end to receive e-mail:

1) Your firewall will need to forward SMTP (TCP 25) and DNS (TCP/UDP 25)
requests to the IP of the server running the corresponding service. Based on
your other posts, that should be the 192.168.1.101.

2) The DNS service (named) will have to be configured to be the SOA (Start
of Authority) for mccorduck.ws so that it can answer queries such as
www.mccorduck.ws or return the MX (mail exchanger) records for mccorduck.ws.
Simply starting named (as supplied by redhat) on your server will not work.
By default, redhat supplies a caching-only name server configuration. If
needed, I can supply you with a DNS/bind template that I use to setup a
proper SOA for your domain.

3) In order to receive e-mail, your server will need an MTA (Message
Transport Agent)installed and configured to accept e-mail for mccorduck.ws.
Redhat supplies two MTA's, sendmail and postfix. Sendmail being the default
MTA that is installed and started. Also, by default, redhat configures
sendmail to only accept port 25 connections from localhost, not from
external sources like the internet. How to configure sendmail to accept
external port 25 connections has been discussed on this list at least a
billion times. Hint: /etc/mail/sendmail.mc, look for DAEMON_OPTIONS.

In addition, remember sendmail is an MTA, not an LDA (local delivery agent).
In other words, sendmail does not store inbound e-mail in your mailbox, the
LDA (procmail) does that. With this in mind, sendmail must be configured to
hand-off any inbound e-mail for mccorduck.ws to the defined LDA. This is
done by adding your domain name to /etc/mail/local-host-names.

Finally, once you get your system configured to accept and deliver e-mail
for your domain, be sure to test it against an open-relay checker. This will
insure that you have not made an inadvertent change to sendmail's
configuration where it accidentaly becomes an open-relay for spammers. There
are many open-relay checkers available on the internet - I have always used
this one: http://www.abuse.net/relay.html

Good Luck
Steve Cowles