Hi,
In hybrid solution , you have two option to create and manage user identity in azure:
- Create cloud only user account. User will be able to access on cloud service without need a account in active directory. This user account can be managed from azure portal
- Install adconnect server , then create user account in on-premise AD. After Adconnect synchronization ,the user account in azure will be created automatically for this user based on his account in on-premise AD. In this case , if you want modify synchronized user account in azure AD , you can't use azure portal , you can do it only from o-premise AD
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