[Today's post comes to us courtesy of Sharique Ahmed and Mark Stanfill]

This article describes how to change the IP addresses of your Windows Essential Business Server (EBS) computers. You can use the Change IP Address Settings Wizard to change the IP address settings of a network adapter on the Windows EBS Management Server, Security Server, or Messaging Server. When you change the IP address settings on one server, the wizard reconfigures connections to the other two servers to keep your network functioning properly. For more information on all the settings that are changed please see http://technet.microsoft.com/en-us/library/d37f87de-5601-4a9f-9487-a79779933100.

Important

• Do not use native tools in Windows Server 2008 to change the IP address settings of a network adapter on a server for Windows EBS. If you already changed IP address settings manually, restore the previous IP address settings, and then follow the steps in this procedure.
• The new IP address setting may affect the connectivity of other computers and devices in your domain, including client computers. If you use the DHCP Server service for dynamic addressing, renew the IP configurations of these computers and devices to update them by running ipconfig /renew. Computers with static IP address assignments may need to have their default gateway or DNS server entries manually modified.
• Changing the IP address settings on a server for Windows EBS briefly interrupts network connectivity. To minimize the impact to the users on your network, change IP address settings during a scheduled service maintenance period.
• You should only run the Change IP Address Settings Wizard on one server at a time.
• There is no Change IP Address Settings Wizard for the Premium Server.
• The Change IP Address Settings Wizard does not update the SCE Managed Computers Group Policy Group Policy object or the System Center Essentials All Computers Policy Group Policy object. You may need to adjust these Group Policy settings to ensure proper network functionality. For more information about modifying Group Policy objects, see the Microsoft Web site (http://go.microsoft.com/fwlink/?LinkID=133100).
• If you replace a Windows EBS server and you configure the IP address settings manually, you need to use the Active Directory Service Interfaces Editor (ADSI Edit) to record these settings in Active Directory. For more information, see the Microsoft Web site (http://go.microsoft.com/fwlink/?LinkID=125622).
• If you move the Management Server and the Messaging Server to a different subnet, do the following on the Security Server.  If no Windows EBS servers exist on the subnet that you are moving from, delete the existing network routes to the subnet you are moving from. To do this, use the following steps:
1. Log on locally to the Security Server as an administrator and open the Forefront Threat Management Gateway (TMG) administration console.
2. Navigate to Forefront TMG (Servername)\Tasks and click on Launch Getting Started Wizard.
3. Click on Configure Network Settings.  Follow the wizard’s prompts until you reach the Local Area Network (LAN) Settings screen.
4. On the Local Area Network (LAN) Settings dialog, delete the static route for your old network.  Add a route for the new subnet as appropriate.
5. Follow the prompts to complete the wizard.
• NOTE:  Never use route add on the Security Server.  Doing so may corrupt TMG’s routing table.

To change the IP address settings of a network adapter on the Management or Messaging Server

1. Log on to the Management Server or Messaging Server with an account that is a member of the Domain Admins group.
2. Click Start, click All Programs, click Windows Essential Business Server, click Tools, and then click Change IP Address Settings.
3. On the Before you begin page, read the instructions, and click Check to test the connectivity from this server to the other two EBS servers. If the wizard cannot connect to one or both of the other EBS servers you cannot proceed.
4. On the Choose IP address settings page, enter your new IP address, subnet mask, and default gateway settings for the network adapter and then click Change.
5. On the Finish page, click Close.

To change the IP address settings of a network adapter on the Security Server

1. Log on to the Security Server with an account that is a member of the Domain Admins group.
2. Click Start, click All Programs, click Windows Essential Business Server, click Tools, and then click Change IP Address Settings.
3. On the Choose a network adapter page, choose the network adapter you wish to modify and click Next.
4. If you have chosen the internal network adapter, click Check to test the connectivity from this server to the other two EBS servers. If the wizard cannot connect to one or both of the other EBS servers you cannot proceed. The step is automatically skipped for the external adapter.
5. On the Choose IP address settings page, do one of the following:
   a. If you are changing the IP address settings of the external adapter on the Security Server, and you want to use the DHCP, click Use DHCP to automatically configure the IP address settings. Then click Change.
   b. If you are changing the IP address settings of the external adapter on the Security Server and you have a static IP address, click Manually configure the IP address settings. Then enter the new IP address, subnet mask, and default gateway. Then click Change
   c. If you are changing the IP address of the internal adapter enter the new IP address, subnet mask, and default gateway. Then click Change.
6. On the Finish page, click Close.

[Updated 12/16/2009 to modify steps for Security server.]