Example: Journaling for Two Mailbox Databases with Distribution List Expansion


Topic Last Modified: 2005-04-27

This example builds on the two earlier examples by adding a distribution list that is expanded on a different server than the server where the message originates. This example also explains other details about how journaling in Exchange works.

Example of journaling for two mailbox databases with distribution list expansion


In this example, UserA sends a message to UserB and the distribution list, DL1. DL1 contains one member, UserC. All users have mailboxes that are journalized. The expansion server for DL1 is on Server02.

As in the earlier examples, Exchange looks up recipient information in Active Directory before sending the message. UserB is recognized and marked as a journalized recipient in the message journaling property. Because the distribution list is expanded on Server02, Server01 cannot determine who is on the distribution list and therefore cannot determine whether the recipients on the list are journalized.

Server01 sends three messages:

  • A message to JournalA on Server03   The journal property on the message specifies UserA as the sender of the attached message to UserB. Server03 attaches this message to the envelope message that it creates for submission to the JournalA mailbox.

  • A message to JournalB on Server04   The journal property on the message specifies UserB as the recipient of the attached message from UserA. Server04 attaches this message to the envelope message that it creates for submission to the JournalB mailbox.

  • A message to UserB on Server02   The message is marked with the journaling property specifying that a journal message has been sent for UserA and UserB; therefore, Server02 does not send a journal message for UserB.

When Server02 receives the message, the journaling property on the message will indicate that it is a journalized message. As the expansion server for the distribution list, DL1, Server02 sends a message to the JournalA recipient mailbox; the message journal property specifies UserC as a recipient. Additionally, because UserC is on Mailbox database B, which is also journalized, Server02 also sends a message to the JournalB recipient mailbox, where Server04 creates an envelope message that specifies UserC as the recipient of a message from UserA.

This example shows that multiple journal messages are frequently sent for a single message. Each of these envelope messages has a different message ID, but the attached message (the original message being journalized) has the same message ID, which is also added to the body of the envelope message. Additionally, if UserB and UserC were on different mailbox stores on Server02, with different journal recipient mailboxes, Server02 would send two messages to the two different journal recipient mailboxes.

Because the sender is identified in the journal properties on the message, Server02 does not have to calculate this as it would in the case where a message is delivered to a hidden distribution list. (Hidden distribution list expansion causes the P1 sender to be changed every time the message is received by a different server.)