Hi @Masi Malmi ,
Thanks for reaching out.
It came to me as a surprise that users from other MS Entra ID tenants need to be added as Guest users to the External ID tenant.
Microsoft Entra External ID is a customer identity and access management (CIAM) solution specifically for consumers and customers.
For any users (consumers/customers) to sign in to application need to sign up to the application.
Similar to Azure AD B2C, for any new users to sign in to application, first that users need to exist in the consumer tenant either by sign up or through invitation.
Microsoft Entra External ID allows users from other tenants to directly sign-up using signUp/signIn user flow and added up as local accounts in consumer tenant. However, you can invite those users through email as well and then those accounts will consider as guest accounts.
I have added two accounts from another tenant one using invite through link and another by sign up using user flow.
The ABC, which is invited through link, is added as guest user type with External Azure AD identities.
However, the other Shweta VRD24 is another account from same tenant which is showing as local account while signing in using CIAM's user flow.
Once these accounts exist in system, you can sign in to your application directly using user flow.
When can we expect to have this OIDC option available? I'm sure a lot of other customers are asking after this as well.
Yes, this is very common ask and our product team is working on it. As of now, we can't share any date.
You can refer https://learn.microsoft.com/en-us/entra/external-id/customers/concept-supported-features-customers for all the current features in External tenant.
Keep checking https://learn.microsoft.com/en-us/entra/external-id/customers/whats-new-docs for monthly updates on external tenant.
Hope this will help.
Thanks,
Shweta
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