The unpacked setting applies per domain. The global setting does mention that it is per AD domain, unfortunately, the Unpacked Backups tab in the Collection properties does not. Enhancement request RMADFE-1072 (to have the documentation and UI description match) has been submitted to Development for consideration in a future release of Recovery Manager for AD.
The algorithm used to determine which backups to unpack is:
- Select a GC from a list of DCs in the domain
- If there is more than one GC, DC selected is random
- One backup per domain is then unpacked
If there is limit for unpacked backups and it is exceeded, the specified number of the oldest backups are deleted. If individual settings are specified for a collection, backups for that particular collection are taken into account, otherwise backups of all collections that use the global settings are taken into account when comparing against the specified limit.