This policy setting determines when a successful DC cache entry is refreshed. This policy setting is applied to caller programs that do not periodically attempt to locate DCs, and it is applied before the returning the DC information to the caller program. This policy setting is relevant to only those callers of DsGetDcName that have not specified the DS_BACKGROUND_ONLY flag.
The default value for this setting is 30 minutes (1800). The maximum value for this setting is (4294967200), while the maximum that is not treated as infinity is 49 days (49*24*60*60=4233600). Any larger value will be treated as infinity. The minimum value for this setting is to always refresh (0).