How to define Exchange 2013 default database for New Mailboxes

[Xavier Mustin]

Just we would need to suspend all the other databases from provisioning and leave the one you want to provision to allow.

Please follow the below cmdlets

Get-MailboxDatabase | Set-MailboxDatabase -IsSuspendedFromProvisioning $true
Set-MailboxDatabase <DatabaseYouWantToUse> -IsSuspendedFromProvisioning $false