As part of your Exchange Hybrid deployment you might introduce new Exchange Servers into your organization. If you’ve planned your deployment correctly, then these will be covered by Hybrid Exchange licences included within your Office 365 Enterprise subscription.
When you don’t need a Hybrid licence
First and foremost, you must consult Microsoft or your licensing specialist for correct guidance for whether you are licensed correctly. However, there is as a key scenario where you will not need to acquire Exchange Hybrid licences.
If you are running Exchange Server 2010, 2013, 2016 or 2019 then you already have Exchange Hybrid capabilities built in to your Exchange Servers today.
Your Client Access services will be used for Autodiscover services and Exchange Web Services based communications. This includes redirecting clients to the cloud, Federated Sharing for Free/Busy and Mailbox Moves. Your Hub Transport services also have the capability built-in to manage Hybrid mail flow between Office 365 and your Exchange Server.
Adding additional servers to your organization to support Exchange Hybrid is a common piece of bad advice shared regularly. If you have a healthy Exchange 2010+ organization today, then you almost certainly have everything you need and will not need to licence Hybrid Servers.
When you do need a Hybrid licence
If you are running Exchange Server 2003 or 2007 you will need to add Exchange 2010 or 2013 servers if you want to perform a Hybrid migration. As those servers don’t have any Hybrid components built-in, then for many organizations it means a part-migration to a newer version of Exchange Server. Typically, this means implementing co-existence with the newer version, and migrating some client-facing services across, such as Autodiscover, Exchange Web Services, ActiveSync and Outlook Anywhere.
It’s important to note that when you add Exchange Hybrid servers to your Exchange 2003/2007 organization you cannot move any mailboxes to the servers if you wish to qualify for a “free” Exchange Hybrid licence. That means you can’t (for example) stage mailboxes from Exchange 2003 to Exchange 2010 first, before moving them to Office 365.
Another key scenario where you are likely to need a Hybrid licence is after you have completed your migration from Exchange Server 2010 to Office 365. After moving your final mailboxes and if you have them, Public Folders, you will decommission Exchange Server 2010. Most organizations will keep Azure AD Connect in place after the migration completes, which means Hybrid Identity (where AD remains the master) is in place. You will therefore require require Exchange Server to manage those attributes – and potentially to relay SMTP email, too. This of course is a great use of an Exchange 2016 or higher server.
Finally – and it comes as a surprise to some organizations – if you have never had Exchange within the organization then you might need to install Exchange Hybrid servers for attribute management within the local AD. As mentioned above – if you use Azure AD Connect, you will have Hybrid identity in place. Many organizations running Domino today and migrating to Office 365 find they need to install an Exchange Hybrid server (or two) and utilize the free Hybrid licence.
Acquiring Exchange Hybrid licences
The process to acquire an Exchange Hybrid licence has recently changed. Previously, you would request Exchange Hybrid licences from the Office 365 portal. This of course, made it easy to request the licences you needed in advance in the same way you licenced Exchange Servers traditionally within your organization.
If you are licensing new Exchange Servers for Hybrid today, the process has changed. You will now licence new Exchange Hybrid servers within the Office 365 Hybrid Wizard.
When you run the Wizard, you will be able to choose the option Licence this server now to apply the Exchange Hybrid licence:
After choosing to licence the server, you’ll be provided with the option to copy product key if you need to apply the Hybrid licence key manually (for example, using the Exchange Admin Center, or PowerShell).