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In Grouper v2.5.25+ there is a feature that allows you to automatically populate groups with recent members of other groups. This is how grace periods are implemented. In v2.5.30+ this changed a bit and is documented below. Note the attributes changed in 2.5.30 and an upgrade task will automatically convert the old format to the new format. When you upgrade you should run the "upgrade task" daemon.
A recent-membership group is a group that contains members who used to be in a certain group a certain number of days ago. You can have multiple recent-membership groups on one group to monitor. (the recentMembershipMarker attribute is assigned to the target group). If a subject is added back to the group to monitor, they will be removed from the recent-membership group. If you want to delegate the ability to assign recent-memberships (by default only admins can do this), just add privileges to the three recentMembership attribute definitions (attr read and attr update).
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