smtp and nat problems

Hello,
I hope this is not OT.
The problem is related to this configuration:

|mailserver|-----|firewall|--------internet

mailserver has private ip address natted to a public ip address by firewall.
Sending mails to certain domains works and to other doesn't.

To troubleshoot the problem, have moved mailserver to dmz, with public ip
address natted for the private lan.

|firewall|------internet
|dmz
|mailserver|

in this case all mails are sent to every domain.

Is there any problem related to smtp and nat or there is some mistake in the
server/firewall configuration ?

thanks in advance
kind regards
Davide


.

Relevant Pages

  • Re: Update dns for local address space
    ... list that as your mailserver, nobody on the internet will know how to ... unless they are also part of your private network. ... reverse lookup on all connections. ... I've never mocked about with DNS in any *nix og *bsd operating systems. ...
    (comp.unix.bsd.freebsd.misc)
  • System.Configuration reading and writing custom section
    ... In my project I use the configuration block from enterprise library. ... Private Properties ... ... private string _sMTPServer; ...
    (microsoft.public.dotnet.framework)
  • Unable to pass an object
    ... a class to hold the configuration data, validate it, save it. ... I have public accessors for all of it. ... private and tried to pass it to a newly ... constructed form via a public method in the sub-form before showing ...
    (microsoft.public.dotnet.languages.csharp)
  • PPPoE Question
    ... I had the configuration on my ASA5505 just the way I wanted it. ... private address on the outside. ... I could not access the Internet through the ASA. ... Is this normal for PPPoE? ...
    (comp.dcom.sys.cisco)
  • Re: Remoting Singleton Issue
    ... client that it doesn't get executed until after you exit the application, ... Adding the configuration as above should fix the problem by ... static void Main ... private System.Windows.Forms.Button button1; ...
    (microsoft.public.dotnet.languages.csharp)