Hybrid IAM with O365 and AWS

MS Expert 

Yes, it is possible to synchronize a single Active Directory (AD) source through Azure AD Connect to multiple Office 365 Azure AD tenants. This is achieved by configuring Azure AD Connect to connect to each of the Azure AD tenants and selecting the relevant directory to synchronize.

When synchronizing multiple tenants with a single AD source, it is important to ensure that the user principal name (UPN) is unique across all tenants. This can be achieved by using a unique domain name for the UPN suffix in each tenant. For example, if the UPN for a user is email address removed for privacy reasons, and you have three tenants, you could configure the UPN suffixes as email address removed for privacy reasons, email address removed for privacy reasons, and email address removed for privacy reasons for each tenant respectively.

Note that when syncing multiple tenants from a single AD source, the configuration can become more complex, and careful planning and testing is required to ensure that the synchronization works as expected. 

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