How the Mailbox Databases Are Updated?

          Database modification is an automated process, it is not directly visible to the administrator or the end user. It is important that you understand how the database is being modified during normal operations.
          The following process takes place when a Mailbox server receives a message:

1. The Mailbox server receives the message. This occurs when the Hub Transport service on the Mailbox server accepts the message from the Front End Transport service that is running on the Client Access server. After the Hub Transport service accepts the message, it is passed to the Mailbox Transport service.
2. Before the message is written to the databases, the Mailbox server writes the message to the current transaction log and the memory cache simultaneously.
3. The Mailbox server writes the transaction from the memory cache to the appropriate database.
4. The Mailbox server updates the checkpoint file to indicate that the transaction was committed successfully to the database.
5. Client servers can access and read the message in the database.