Postfix configuration with Windows DNS

We are running Windows 2003 domain, now get a new linux server for intranet mail only (smtp and pop3).

Suse Enterprise Server                                      Windows AD DC server with DNS
hostname: sv2                                                  hostname: sv1
domain:                                           domain: (AD)
IP           :                          
Subnet    :                        
Gateway  :                           
DNS        :                          

- Postfix configured
# postconf
myhostname =
mydomain =
myorigin = $myhostname
mydestination = $myhostname, $mydomain
inet_interfaces = all
mynetworks =,, hash:/etc/postfix/access
mynetworks_style = subnet
#postfix check (no error)

- qpopper installed for POP3 service

- Firewall opened for SMTP SERVER and POP3 SERVER

# mail user1
Subject: Test

- Use OUTLOOK EXPRESS to take a mail from Suse linux server from one desktop (
Mail received, it's fine (,
Reply (, Sent failed.

1. If our Windows domain name "", can I use it for linux server domain name as my above setting ?

2. My prostfix configuration is correct ?  If I can use 'mail' command to send mail to one of account, is the postfix setup successfully ?

3. "# mynetworks_style = subnet" on main.conf, but why still display "mynetworks_style = subnet" by postconf command ?

4. In fact, the failure is come from Winodws side DNS ? how to set ? (I just add HOST name "" into Windows' DNS)

5. Any further comment please ?

Thanks help !

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1.  Yes you can, and your configuration looks correct. I have run such a combination and it worked :)

2. Your postfix configuration is correct when it does what you want. I don't think that using the local mail command is enough to test your complete configuration: Try testing with clients and sending email from for example your hotmail account.

3. As it is the default setting (

4. Uhh where are your MX records??? as i don't see an,y the error will continue to exist as you need an dns record to forward your to In your words this error is indeed your dns server configured wrong

5. For postfix: At least read this thoroughly:
 and this is about the DNS records:


rhinocerosAuthor Commented:
Just also take a testing again
From SUSE side
# mail  (failed)                 --> Why failed ? I need it for sending from client
# mail  (succeeded)
# mail     (To Exchange Server - succeeded)

From Exchange to, and (failed)


DNS setting:
- Forward Lookup Zones
     - (same as parent folder)   Mail Exchanger [20]
     - it                                   Alias                  
     - sv2                                Host                  

Reverse Lookup Zones
   - 192.168.1.x Subnet
     -                  Pointer                

Any idea pleae ?

Thanks !

rhinocerosAuthor Commented:
DNS setting:
- Forward Lookup Zones
     - (same as parent folder)   Mail Exchanger [20]
     - it                                   Alias                  
     - sv2                                Host                  

Reverse Lookup Zones
   - 192.168.1.x Subnet
     -                  Pointer                

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rhinocerosAuthor Commented:
One more, I can telnet port 25 on localhost, but failed to telnet from outsider ???

(I have stopped the firewall for testing)
rhinocerosAuthor Commented:

1. I don't know why ""  is not like normally linux file, it has many parameters stored at the bottom of file

myhostname =
inet_interfaces = :: 1
mynetworks_sylte = subnet

The setting has been overlapped. So why I also changed inet_interfaces=all, it's still restricted interfaces on locally.

2. One more, we are able to receive mail by as we want, when changed $myhostname = So far, we think that must use fully-qualified domain name for $myhostname ($ However, just look for some documents to answer my question...

My own hostname
The myhostname parameter describes the fully-qualified domain name of the machine running the Postfix system. $myhostname appears as the default value in many other Postfix configuration parameters.

By default, myhostname is set to the local machine name. If your machine name is not in fully-qualified domain name form, or if you run Postfix on a virtual interface, you will have to specify the fully-qualified domain name that the mail system should use.


myhostname = host.local.domain (local hostname is not FQDN)
myhostname = host.virtual.domain (virtual interface)
myhostname = virtual.domain (virtual interface)


Overall, the problem was not come from Windows DNS resolving

Anyway, thanks for your help indeed !

PAQed with points refunded (125)

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