You are using the enhanced GUP features in Symantec Endpoint Protection (SEP), but some of the behavior you are seeing may either not be as expected, or, you would like to have more information on the different options.
For details please refer to "New features and functionality in Symantec Endpoint Protection Release Update 5 (SEP RU 5) Group Update Provider (GUP)"
Identifying the GUP Types on the Local SEP Client
To verify if the SEP client is configured to use a GUP or not, you can check the following Registry Key:
[HKEY_LOCAL_MACHINE\SOFTWARE\Symantec\Symantec Endpoint Protection\LiveUpdate
A dword value of 00000001 indicates that at least one GUP is configured.
To identify the GUP type there is an additional key:
An IP address or computer name indicates that a "Single GUP" was configured.
This is the equivalent of the following configuration settings in SEPM:
If the "MasterClientHost" has an empty value, then "Multiple Group Update Providers" was configured without the optional "Group Update Provider on a different subnet" setting.
This is the equivalent of the following configuration settings in SEPM:
It is a little bit more difficult to determine if "Backup" Group Update Provider on a different subnet is configured. The Registry settings are almost identical to the Single GUP configuration:
[HKEY_LOCAL_MACHINE\SOFTWARE\Symantec\Symantec Endpoint Protection\LiveUpdate
An IP address or computer name indicates that a GUP was configured. The difference with the Single GUP entry is that the IP address should belong to a computer that is in a different subnet than this SEP Client computer.
This is the equivalent of the following configuration settings in SEPM:
From a local client configuration perspective the only difference between "GUP from a different subnet configured as a Single GUP" and the "Backup Group Update Provider on a different subnet" is that the Single GUP in this case would be the only GUP available to the client, whereas the "Backup" GUP is exactly that: just a backup. The client should have Multiple local GUPs available.