Supporting Messaging Clients

Create an External DNS List

When resolving names for non-local message delivery, SMTP virtual servers will query all DNS servers configured in Windows 2000 for all network interfaces. If your Exchange server has interfaces on both internal and external (Internet) networks, the potential mix of internal and external DNS servers is not recommended. An external DNS server could be queried to resolve an internal host name, for example; if this happens, e-mail flow within your organization could be affected by DNS servers outside your intranet. You can, however, create a list of external DNS servers for resolving names in remote domains. Whenever a message intended for a non-local recipient is received, the SMTP virtual server will automatically consult this list.

Note   After the external DNS server list is created, the SMTP virtual server only uses the servers on that list. If you want to keep using some or all of your local DNS servers, you need to manually add those IP addresses to the list.

To create an external DNS list:

  1. Start System Manager
    On the Start menu, point to Programs, point to Microsoft Exchange, and then click System Manager.
  2. Navigate to the SMTP virtual server.
    1. Servers
    2. Server
    3. Protocols
    4. SMTP
    5. SMTP virtual servers
    6. SMTP virtual server
  3. Right-click the SMTP virtual server, and then click Properties.
  4. On the Delivery tab, click Advanced.
  5. In Advanced Delivery, click Configure.
  6. In Configure, click Add, type the IP address of a DNS server, and then click OK. Repeat this step for every server you want to add to the external DNS list.
  7. Highlight a server in the list, and then click Move Up and Move Down as necessary to set the order. The SMTP virtual server will start with the top DNS server and descend the list until one of the servers returns the information it needs.
  8. Note   To remove a server from the list, highlight it, and then click Remove.

Related Topics

Intranet-to-Internet Communication