FW: DNS question

[David T. Ashley]

-Original Message-
From: David T. Ashley [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, March 28, 2001 6:55 AM
To: [EMAIL PROTECTED]
Subject: DNS question


I read the HOWTO for q-mail, but there is one thing I don't understand.

It states that I need a DNS and that my machines have to be listed in the
DNS for qmail to work.

I have a hardware firewall (one of those $150 boxes) guarding my DSL line
with a static IP.  Is it good enough that my static IP has a reverse-DNS
resolution, or do my "internal" addresses need to resolve as well.  For
example, my static IP is 64.129.57.5, but the server (internally, behind the
firewall) is 192.168.0.33.  Clearly, trying to reverse-DNS the latter will
lead to trouble, whereas the former is OK.

It isn't clear to me what is meant by the statements about DNS in the HOWTO
or what qmail needs to be viable.

Any insight would be appreciated.

Thanks, Dave.

Re: FW: DNS question

[Frank Tegtmeyer]

 firewall) is 192.168.0.33.  Clearly, trying to reverse-DNS the latter will
 lead to trouble, whereas the former is OK.

You are using NAT - if you only want to send email from your internal
network to the world and get your mails by "polling" it somehow you get no 
problem (except that your netblock may be blocked by some mail servers).

If you want to provide services like smtp to the world you have two 
choices:

a) establish that service on your NAT box (I assume it's impossible on 
   that $155 box)

b) your box must be able to redirect defined ports to hosts at your 
   internal network. Most NAT devices can do that, some cannot.

Regarding DNS:
If you provide services to the world always the address of your firewall 
box is visible to the world. Your internal addresses don't matter.

Regards, Frank