Exchange 2016 – Unable to add database copy
One of the issues on Exchange server 2016 when creating a new DAG and try to add a database copy you may receive the following error
“The seeding operation failed. Error: An error occurred while running prerequisite checks. Error: The specified database isn’t configured for replication and therefore cannot be used to perform seed operations”
The error you encountered is often caused by AD replication issues. Since you have multiple DCs, this issue could occur when the value of the ConfigurationDomainController parameter and the value of the PreferredGlobalCatalog parameter are different.
In this scenario, the Mailbox database operation fails because of the replication latency that occurs between the configured domain controllers and the preferred global catalog.
You can try to set static entry to use same DC/GC:
“Set-ExchangeServer –Identity <mailboxserver_name> -StaticDomainControllers <DC FQDN> -StaticGlobalCatalogs <DC FQDN> –StaticConfigDomainController <DC FQDN>”.
Ratish Nair
Microsoft MVP | Office Servers and Services
Team @MSExchangeGuru