What If All Gc In The Environment Are Down ?

1.	What If All Gc In The Environment Are Down ?
Answer» GC is required for multi DOMAIN forests - In a single domain infrastructure, the DCs will not contact the GC for authenticating. But in multi domain infrastructure, GC is required for AUTHENTICATION. Universal GROUP Membership EVALUATION - Universal Group Membership which exists in a multi domain forests works only with GC. UPN resolution - The users cannot login to the domain using the username abc@example.com

Answer»

GC is required for multi DOMAIN forests - In a single domain infrastructure, the DCs will not contact the GC for authenticating. But in multi domain infrastructure, GC is required for AUTHENTICATION.
Universal GROUP Membership EVALUATION - Universal Group Membership which exists in a multi domain forests works only with GC.
UPN resolution - The users cannot login to the domain using the username abc@example.com

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