Upgrading the Network Load Balancing cluster

Applies To: Windows Server 2008

Some common scenarios for upgrading a Network Load Balancing (NLB) cluster are described in this section.

In-place upgrades

In this scenario, you have a Windows Server 2003 NLB cluster with one or more virtual IP addresses and want to upgrade the cluster to Windows Server 2008 while preserving the current cluster configuration and with minimal interruption of service to clients.

To perform a rolling upgrade from a Windows Server 2003 NLB cluster with one or more virtual IP addresses

1. Upgrade the first group of selected nodes in the cluster. You should select a number of nodes that is between 1 and N-1 (for an N node cluster) making sure to exclude some Windows Server 2003 nodes to allow the NLB cluster to continue responding to client requests. For each node you have selected to upgrade, you should first drainstop the node to make sure that any pending client requests are addressed before proceeding with the upgrade. For more information, see Disable new traffic handling for specific ports and stop Network Load Balancing. In addition, the initial host state must be set to Stopped.

2. After the upgrade process is complete, you should verify that the application that is load balanced is working properly with the dedicated IP address. You can then change the initial host state back and start NLB on that node.

3. After the first group of nodes finishes upgrading, open NLB Manager on one of the Windows Server 2008 nodes and connect to the local cluster. Confirm that all of the upgraded nodes:

   • Remain as part of the NLB cluster

   • Are in the converged state

   • Are properly handling network traffic

   After upgrading a node, you may discover that NLB is no longer bound to the network adapter on the node. If so, you must rejoin the node to the NLB cluster and reconfigure any static network configuration that was lost during the upgrade.

4. Upgrade the remaining nodes in the cluster to Windows Server 2008. At this point in the upgrade process, the Windows Server 2008 nodes should be handling client requests. For each node you have selected to upgrade, you should first drainstop the node to make sure that any pending client requests are addressed before proceeding with the upgrade. In addition, the initial host state must be set to Stopped.

5. Repeat Step 3 after the upgrade is complete.

IPv4 to IPv6 upgrades

In this scenario, you have a Windows Server 2003 NLB cluster with one or more IPv4 virtual IP addresses and want to upgrade the cluster to Windows Server 2008. In addition, you want to create one or more IPv6 virtual IP addresses to handle IPv6 traffic. You may also want to discontinue handling IPv4 traffic and switch to an IPv6-only environment.

To perform a rolling upgrade from a Windows Server 2003 NLB cluster with one or more IPv4 virtual IP addresses to a cluster with both IPv4 and IPv6 virtual IP addresses or to a cluster with only IPv6 virtual IP addresses

1. Follow the procedure for performing a rolling upgrade from a Windows Server 2003 NLB cluster with one or more virtual IP addresses in In-place upgrades.

2. After all NLB cluster hosts are upgraded to Windows Server 2008, you should confirm that all network adapters in the cluster have IPv6 enabled, in addition to having IPv4 enabled. This is the default setting.

3. You can now create new IPv6 virtual IP addresses on the cluster.

4. Optionally, you can now stop handling IPv4 traffic by removing all IPv4 virtual IP addresses from the cluster and disabling IPv4 on all cluster hosts. You will now have a IPv6-only cluster environment.

Server Core upgrades

In this scenario, you have a Windows Server 2003 NLB cluster with one or more IPv4 virtual IP addresses and want to upgrade the cluster to Windows Server 2008 Server Core while preserving the current cluster configuration and with minimal interruption of service to clients.

Upgrading from Windows Server 2003 to Windows Server 2008 Server Core is not allowed. You may only run a clean installation of Windows Server 2008 Server Core, or upgrade from the Server Core beta releases to a newer Server Core release.

Windows Server 2008 Server Core nodes do not have GUI-based administrator tools, such as NLB Manager. In addition, nlb.exe and other command-line tools do not support the creation of NLB clusters. Windows Server 2008 Server Core NLB clusters can only be managed using NLB Manager from a separate computer running either Windows Server 2008 (using the NLB feature or RSAT) or using RSAT.

To perform a rolling upgrade from a Windows Server 2003 NLB cluster to Windows Server 2008 Server Core with one or more IPv4 virtual IP addresses

1. Remove the first group of selected nodes from the Windows Server 2003 cluster. You should select a number of nodes that is between 1 and N-1 (for an N node cluster).

2. Run a clean installation of Windows Server 2008 Server Core on the nodes you just removed from the cluster.

3. After the installation is complete, open NLB Manager on a separate computer that is running either Windows Server 2008 (using the NLB feature or RSAT) or ) or using RSAT and connect to the Windows Server 2003 NLB cluster.

4. Add the nodes on which you just installed a clean installation of Windows Server 2008 Server Core to the Windows Server 2003 NLB cluster.

5. Confirm that all of the upgraded nodes:

   • Remain as part of the NLB cluster

   • Are in the converged state

   • Are properly handling network traffic

   The Windows Server 2003 nodes should still be included in the cluster.

   After upgrading a node, you may discover that NLB is no longer bound to the network adapter on the node. If so, you must rejoin the node to the NLB cluster and reconfigure any static network configuration that was lost during the upgrade.

6. Remove the remaining group of Windows Server 2003 nodes from the cluster.

7. Repeat Steps 2-5 for the remaining group of nodes.