Change in Physical IP address causes mail flow issues
Changing the IP address of windows server manually which has Exchange 2000 or Exchange 2003 installed would cause the mail flow to stop from external servers.
Customer’s normally find the problem with connecting to port #25 after changing the IP address on the Exchange 2000 and Exchange 2003 servers, if the SMTP Virtual sever was bound to a specific IP and this could cause all inbound mails to the Exchange server to stop.
For Example, Let’s consider an Exchange Server on which the SMTP Virtual Server is bound to a specific IP address. When we change the IP address from the network connections without changing the Exchange SMTP VS configuration, will result in this problem.
This issue is caused due to the changes made to the Default SMTP Virtual server on the Exchange 2000 and Exchange 2003 servers, which gets updated to Active Directory directly and then to IIS metabase. But this will not work as expected for SMTP virtual server IP address change, where the IP address is manually altered through the network connection on the Exchange 2000 / 2003 server.
To Work around this issue, we have 2 ways:
==============================================================================================================
A) For Exchange 2000 or Exchange 2003 server.
Manually change the Default SMTP virtual server IP address configuration to use the new IP address assigned to system or change it to “All Unassigned” under General tab and restart Simple Mail Transfer Protocol service.
How to change an IP Address configuration to use new IP address or “All unassigned” for Exchange 2000 or Exchange 2003 SMTP Virtual server:-
To assign an IP address to your SMTP virtual server, follow these steps:
1. On the Start menu, point to Programs, point to Microsoft Exchange, and then click System Manager.
2. Double-click Administrative Groups.
3. Double-click First Administrative Group.
NOTE: If you have changed the name of the default administrative group or Installed the exchange server in other administrative group, expand the appropriate node for that administrative group.
4. Double-click Servers and Protocol container and find the default SMTP virtual server on any server.
Click the virtual server that you want to configure.
5. On the Action menu, click Properties.
6. On the General tab, click to select either new IP address assigned or “All Unassigned” from the drop down.
7. Finally restart the Simple Mail Protocol Service.
8. Test the SMTP connectivity using telnet command.
==============================================================================================================
B) For IIS SMTP server.
Manually changing the IP address under network connection resets the SMTP virtual server IP configuration from the assigned IP address to “All Unassigned”. But it will not allow any connection with new or old IP addresses.
Change the SMTP virtual server IP configuration to use the new IP address and then restart the SMTP service to connect using new IP address.
How do we change IP Address configuration for IIS SMTP virtual server.
To assign an IP address to your SMTP virtual server, follow these steps:
1. Click Start, point to Programs, point to Administrative Tools, and then click Internet Services Manager. Alternatively, start the IIS snap-in.
2. Right-click on Default SMTP Virtual Server, and then click Properties.
3. Click the General tab. Assign the new IP address to the SMTP virtual server to respond to connection requests.
4. Finally Restart the Simple Mail Protocol Service.
5. Test the SMTP connectivity using telnet command.
==============================================================================================================
Repro Steps
1. Repro for Exchange 2003 server And also attaching the snap shot for your reference.
On the Start menu, point to Programs, point to Microsoft Exchange, and then click System Manager.
2. Double-click Administrative Groups.
3. Double-click First Administrative Group.
NOTE: If you have changed the name of the default administrative group or Installed the exchange server in other administrative group, expand the appropriate node for that administrative group.
4. Double-click Servers and Protocol container and find the default SMTP virtual server on any server.
5. Click the virtual server that you want to configure.
6. On the Action menu, click Properties.
7. On the General tab, click to select IP address assigned for the system from the drop down box.
8. Restart the Simple Mail Protocol Service.
9. Test the SMTP connectivity using telnet command. ( it will connect successfully)
10. Click Start, point to Control Panel , and click Network Connections
11. Right-click the local area connection that you want to modify and then click Properties.
12. In the This connection uses the following items box, click Internet Protocol (TCP/IP) , and then click Properties . The Internet Protocol (TCP/IP) Properties dialog box appears.
13. Change IP address and close the window and reboot the box if requested.
14. Test the SMTP connectivity using telnet command. ( it will fail to connect)
More Information
=============
SMTP virtual server on standalone windows 2000 servers automatically changes SMTP Virtual server IP configuration to use “All Unassigned” if we change the IP address manually in Network Connection, but would again result in the above problem.
Srinivas Santhanam,
Senior Support Engineer, Exchange Server Team
Reviewed by
Arindam Thodkar,
Support Escalation Engineer, Exchange Server Team