Last I recall, Windows update is signed in such a way that it is hard to imitate it. You may be able to use a caching proxy server to actually hold current updates but I am not sure the windows update clients will accept them without having their registry patched.
WSUS 3+ runs as its own service now. DHCP/DNS and all that has to be handled separately.
Registry entries I am referring to:
http://thelazyadmin.com/blogs/...-Active-Directory.aspx
HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\WindowsUpdate
These five settings control the WSUS enviroment.
* WUServer: Defines the location of the WSUS Server - RegString -
http://wsus_server_name
* WUStatus: Defines the location of the WSUS Status Server - RegString -
http://wsus_server_name
* TargetGroupEnabled: Enables (1) or disables (0) client side targeting - Reg_DWORD - 1 or 0
* TargetGroup: Defines the name of the target group - Reg_String - Groupname
* ElevateNonAdmins: Enables (1) or disables (0) non-admin users from controlling what updates get installed. - Reg_DWORD - 1 or 0
The next set of options configures Automatic Updates on the client. These options are located in the registry under
HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\WindowsUpdate\AU
There are alot of options but I am only going to cover the main ones.
* AUOptions: Automatically download and schedule installation. - Reg_DWORD - 4
* ScheduledInstallDay: The day of the week to install the downloaded hotfxes, 0 = everday. - Reg_DWORD - 0
* ScheduledInstallTime: The time of day to install the downloaded hotfixes, n = hour (0-23) - Reg_DWORD - 3 (3:00 AM)
* DetectionFrequencyEnabled: Enables (1) or disables (0) the detection frequency interval - Reg_DWORD - 1
* DetectionFrequency: Specifies the detection frequency interval, n=hours (0-22) - Reg_DWORD - 22
* NoAutoRebootWithLoggedOnUsers: Prevents Automatic Updates from rebooting the computer if a user is logged in. If set to 1 the user will be prompted to reboot, if set to 0 the user will be warned that the PC is rebooting in 5 minutes. - Reg_DWORD - 1
* UseWUServer: This must be present and set to 1 in order for the WSUS Enviroment values to be used. - Reg_DWORD - 1
Make sure that you revert the settings also... if you don't they will never auto patch on their own anymore. The update site however will work.
Also WSUS is designed for auto deployment, you have to issue command line commands to force the clients to try and locate updates and then to patch. "windowsupdate.com" is still windowsupdate.com. Also the update client will not patch more than I think 10 updates at a time so if you have 60+ expect to let the machine sit there and reboot.
WSUS will not deploy initial installs of of things like .net. You must download the admin copy and install it before WSUS will patch it.