"Secondary sites can no longer be installed from the SCCM setup. They must be installed from the console. These are the available options presented by setup"
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"If you need to control SCCM traffic from a site server to another location, you can now use the SCCM 2012 distribution point, which includes throttling and scheduling features. You would only need
a secondary site if you also need to control traffic sent from client systems to the site server, as the secondary site has a Management Point. The PXE server role is now part of the Distribution Point. Secondary sites and other system roles have
to be manually uninstalled from the SCCM 2007 hierarchy and redeployed on the SCCM 2012 hierarchy."
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