You would like to set it so the Symantec Endpoint Protection (SEP) clients only download definitions from the Symantec LiveUpdate servers.
1. In the Symantec Endpoint Protection Manager (SEPM) go to -> Policies -> LiveUpdate.
2. Edit the LiveUpdate Settings Policy you would like to change.
3. In Server tab Uncheck "Use the default management server" and ensure "Use a LiveUpdate server" is checked along with "Use the default Symantec LiveUpdate server":
4. Click on the Schedule tab and uncheck both options under "Options for Skipping LiveUpdate":
5. Click OK, Save and assign the Policy to the groups/locations that should go only to Symantec LiveUpdate servers.
Both the Mac and Linux LiveUpdate policy settings default to retrieving LiveUpdate content from the Symantec LiveUpdate server.