Extension Attributes Deselecting in AAD connect

[Steve Ritchie]

I have a client where we have implemented AAD Connect to sync on prem AD to Office 365 and now they are concerned that some extension attributes (from exchange on prem) contain values that should not be synchronised to Office 365. I know you can deselect those extension attributes but is there any reason that Office 365 actually needs them so there could be a potential issue if we deselect any? we are only looking to exclude around 5 extension attributes.

I want to give the client confidence that we can deselect extension attributes without harming the service.

https://azure.microsoft.com/en-gb/documentation/articles/active-directory-aadconnectsync-attributes-...

Thank you for any help.

[#2]

No, O365 does not depend on any of these. They are totally optional to sync.

Here's a detailed list of which attributes are synced per service: https://azure.microsoft.com/en-us/documentation/articles/active-directory-aadconnectsync-attributes-...

[#3]

Thank you for the reply. Appreciate that. Just to confirm also, we have Exchange 2013 Hybrid in place so absolutely no issues with removing some extension attributes from the sync in relation to that?

[#4]

I agree, even with Exchange 2013 Hybrid, it should not cause issue. However, to ensure these attributes are not synced in the future after an update to Azure AD Connect or re-install, ensure you document the change to the configuration properly.

Steve