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DMZ to DMZ and DMZ to Outside DNS Alias Command

I have a web server on my DMZ which I have configured properly to host clients using NAT and static translation. I can view my hosting accounts from my Inside interface using the public IP and host through the configuration of aliases without DNS doctoring but when I want to open up a browser from my DMZ and view the hosting accounts from the DMZ I can not do this. I tried DNS doctoring using the Alias command but it still does not work.

I am running both my DNS server in the DMZ and everything works just fine for access from the outside to DMZ and from Inside to DMZ but I have no access from DMZ to DMZ hosted IP addresses or hosts. I just want to be able to open up the browser or command prompt and either access the websites from the browser on the DMZ or ping the host nhames from the command prompt on the DMZ.

THe problem is that I have a web server which uses CDONTS to send emails from IIS5 and CDONTS requires that I put the mail server host in the settings. Well since the mail server is nated with a public IP address to a private one when the CDONTS/IIS5 tries to send the email it tries to contact the mail server but the firewall rejects the communication because it will not let any traffic out with the destination of the public IP address until I set up a rule for the DMZ to be able to do this. I have implemented this with no problem in my Inside interface and I can access all email and websites hosted from the DMZ with no problems through aliases but it does not want to work from DMZ to DMZ.

Sorry for the long email but I thought I would provide as much explanation as possible.

Does anyone know how to get this done.


Benjamin Saenz

Network Administrator


  • Other Security Subjects

Re: DMZ to DMZ and DMZ to Outside DNS Alias Command

Often times complex troubleshooting issues are best addressed in an interactive session with one of our trained technical assistance engineers. While other forum users may be able to help, it’s often difficult to do so for this type of issue.

To utilize the resources at our Technical Assistance Center, please visit and to open a case with one of our TAC engineers, visit

If anyone else in the forum has some advice, please reply to this thread.

Thank you for posting.