When a Microsoft 365 organisation signs up, it gets an onmicrosoft.com domain that serves as the default for usernames and mail routing. You can switch the fallback role to a different onmicrosoft.com domain, but these domains can never be deleted and each tenant may hold at most five of them.
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Terms in this definition
- Microsoft 365
Formerly Office 365, Microsoft's software-as-a-service productivity suite. A Microsoft Entra tenant provides its identity, and its data is not governed by Azure RBAC.
- Initial domain
The domain in the form <name>.onmicrosoft.com that each Entra tenant receives at creation; it cannot be deleted or altered.
- Geographic
A Traffic Manager routing method that picks the endpoint according to where the user is located geographically.
- SWITCH
Checks one expression against several candidate values, returning whichever result pairs with the match (or a fallback otherwise). Writing SWITCH ( TRUE (), ... ) avoids nested IF chains: whichever condition is first true wins.
- Fallback
When a request fails with an error like 429 or 5xx, this Unity Gateway option tries alternative destinations one after another in the order configured. Only the first choice of destination comes from traffic splitting; retries ignore the split.
- Role
How an actor normally or expectedly behaves, or the part a person takes in a process. A single actor may hold more than one role.
- Tenant
A trusted, dedicated Microsoft Entra ID instance that stores the users, groups and app registrations of one organisation. A subscription trusts only a single tenant, although a tenant can be trusted by several subscriptions.