In large MIM environments a Full Synchronization on objects in a Connector Space can take a very long time. In some environments we talk about many hours. In some cases it’s better to only synchronize selected objects in the Connector Space to avoid the downtime caused by the Full Synchronization.
A bit of a warning before we move along… When MIM tells you it wants to run a Full Synchronization and you select to not doing it, you need to be sure it’s not needed or you can end up in a situation where you see Delta Synchronization not working as expected… with that said, there are situations where you know it’s safe.
So when you for example add or change a Synchronization Rule MIM will tell you a Full Synchronization is required. But if you know that the change is only affecting a limited number of objects, like when using scoping filters, you can instead choose to only synchronize the affected objects and then clear the Full Synchronization warning MIM gave you.
I have created a small example script on how you can do this on my gist.
When you are done with the synchronization of your selected objects you use the Clear-FullSyncWarning command from LithnetMIISAutomation powershell module to have MIM stop complaining about the need for the Full Synchronization.