1. Hybrid Exchange
We recommend to sync to the on-premise Active Directory of an hybrid Exchange environment. You can configure the Microsoft tool „Azure Active Directory Connect (AADC)“ formerly: „Directory Synchronization (Dirsync)“, so it will synchronize the imported mail-contacts to the Office 365 tenant of the hybrid Exchange environment.
Note: Mail-enabled objects, which are only the Office 365 tenant, can be exported bei GALsync in a separate export policy from the Office 365 tenant, if it is necessary.
2. Exchange Cloud Only
GALsync can directly synchronize with an Office 365 tenant in an Exchange cloud-only scenerio via remote PowerShell.
3. Exchange cloud-only with an hybrid Active Directory
In an Exchange cloud-only scenerio is a hybrid Active Directory possible. GALsync can directly synchronize with an Office 365 tenant and has an export option for Mastered-On-Premise objects in the Office 365 tenant.