Migrate from a SUS Server to a WSUS Server
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2, Windows Server Update Services
This section discusses migrating from a Software Update Services (SUS) server to a Windows Server Update Services (WSUS) server. The "Windows Server Update Services Operations Guide" includes other types of migration documentation, such as migrating from MSDE or WMSDE to Microsoft SQL Server, or moving the WSUS database from one SQL server to another SQL server.
WSUS is the next iteration of SUS. Although you cannot upgrade a SUS server to a WSUS server, there is support for migrating your approvals and updates from SUS to the new WSUS server. This ensures that you do not have to download the same updates twice, nor spend time approving previously approved updates. If you are using multiple SUS servers to target updates to computers fulfilling specific roles on the network, you can map SUS approvals to WSUS computer groups as you migrate the approvals. This allows you to consolidate multiple SUS servers on a single WSUS server.
It is simple to introduce WSUS into your production environment. You can install WSUS and SUS on the same computer and both will function. You can also have SUS and WSUS environments running simultaneously on your network. However, you can never synchronize a SUS server with a WSUS server or vice versa. Beyond the migration, the two update solutions are completely isolated from one another. This enables you to test WSUS in your production environment while relying on SUS to update client computers. When WSUS testing is complete and you are comfortable with the new solution, you can decommission SUS.
There are some limitations to SUS-to-WSUS migration. Migration is only for approvals and updates on the SUS server. You cannot migrate anything else, such as proxy-server or IIS settings. These types of configuration tasks must be completed independently on the WSUS server. Also, migration is a one-way process; you cannot migrate from WSUS back to SUS.
Also note that if approvals are created on the WSUS server before approval migration is performed, the explicitly created approvals are overwritten by the migration of approvals.
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