Before you can provision Exchange services for an organization, you must first register the appropriate Exchange resources with Resource Manager. Exchange resources consist of disk space used for mailbox stores and mailboxes. You register resources either by using Delegated Administration Console or by submitting a direct XML request. Once you register a resource with Resource Manager, it keeps track of the status of the resource.
It is recommended that you verify the available disk space before registering it. Resource Manager will accept any amount of disk space that you specify, whether or not it is available on the physical disk. Resource Manager will then provision all of the disk space you registered, even if it is not available. This can result in errors when organizations attempt to use the disk space for mailboxes.
When you submit a provisioning request to enable Exchange services for an organization, Microsoft Provisioning System queries the Resource Manager database to find an Exchange server resource that has sufficient disk space to accommodate the size of the requested mailbox store. It then creates the mailbox store on the Exchange server, and updates the Resource Manager database with information about the disk space used and the organization to which it was allocated.
Resource Manager keeps track of the total disk space consumed by an organization's mailboxes. This amount cannot exceed the size of the mailbox store allocated to the organization. In order to create a new mailbox, sufficient disk space must be available in the organization's mailbox store. When you create a mailbox for a user account, the disk space allocated to the mailbox is deducted from the organization's mailbox store. If there is not sufficient disk space available in that organization's mailbox store, the operation fails, and an error message is returned.
When you delete a mailbox or disable Exchange services for an organization, Microsoft Provisioning System updates the Resource Manager database to release the associated disk space so it can be used to provision another mailbox or organization.
For more information about Resource Manager, see Resource management. For more information about registering Exchange resources, see Working with Exchange resources. For specific procedures on registering Exchange resources, see "Register Exchange resources" in the installation documentation located in the root folder on the Microsoft Provisioning System product CD. For a single computer configuration, see install_single.htm. For a multi-computer configuration, see install_multi.htm. For specific procedures on creating mailboxes, see Set up Exchange mailboxes.