XADM: Controlling Public Folder Hierarchy Status Messages

This article describes how to control public folder hierarchy status messages.

Public folder status messages for hierarchy objects are sent and received by every server that has a public information store in an Exchange Server organization. This hierarchy status message is used to keep changes to the public folder hierarchy, Internet newsgroup hierarchy (Exchange Server 5.0 and 5.5 only), system folder hierarchy (offline Address Book, Free/Busy folder, and so on), and the Events Configuration folder (Exchange Server 5.5 only) synchronized with all of the public information stores across the organization.

By default, these hierarchy status messages are sent once a day. Any Exchange Server computer in the organization that has a public information store sends a status message for each of the public folder hierarchy objects that are listed in the following sections to every server in the Exchange Server organization that has a public information store.

Folder Hierarchy

This is the hierarchy of public folders as seen by the user. One message is sent at each 24-hour interval by default. You can identify this message in the Microsoft Windows NT Event Viewer Application event log (when "Replication Outgoing Messages" diagnostic logging for the server's public information store is set to maximum) by looking at the description of the event ID 3017 message. The description for the folder hierarchy status message is similar to the following: NOTE: The message ID will differ.

System Folders Hierarchy

This is the hierarchy of the system folders. The system folders consist of the offline Address Book, the Free/Busy folder, and the Organizational Forms folder. One message is sent at each 24-hour interval by default. You can identify this message in the Windows NT Event Viewer Application event log (when "Replication Outgoing Messages" diagnostic logging for the server's public information store is set to maximum) by looking at the description of the event ID 3017 message. The description for the system folder hierarchy status message is similar to the following: NOTE: The message ID will differ.

Internet Newsgroups Hierarchy (Exchange Server 5.0 and 5.5 Only)

This is the hierarchy of Internet newsgroup Network News Transfer Protocol (NNTP) folders as seen by the user. One message is sent at each 24-hour interval by default. You can identify this message in the Windows NT Event Viewer Application event log (when "Replication Outgoing Messages" diagnostic logging for the server's public information store is set to maximum) by looking at the description of the event ID 3017 message. The description for the Internet newsgroup folder hierarchy status message is similar to the following: NOTE: The message ID will differ.

Events Configuration Hierarchy

This is the hierarchy of Events Config folders. One message is sent for each events folder in the hierarchy at each 24-hour interval by default. You can identify this message in the Windows NT Event Viewer Application event log (when "Replication Outgoing Messages" diagnostic logging for the server's public information store is set to maximum) by looking at the description of the event ID 3017 message. The description for the Events Config folder hierarchy status message is similar to the following: NOTE: The message ID will differ, and the server name changes for each folder in the hierarchy.

For these outgoing hierarchy status messages, every server that has a public information store is considered a recipient of the message. Each recipient adds size to the hierarchy status message. Therefore, the more servers that have public information stores in the organization, the larger the status message is.

In Exchange Server organizations that contain many servers that are configured with public information stores, the traffic that is generated for these hierarchy status messages can have a significant impact, especially if there are many low-bandwidth network connections.

For example, in an Exchange Server 5.5 organization that contains two sites, each with five servers, if all of the servers have public information stores, approximately 80 hierarchy status messages are sent through the organization at either 12:15 A.M. Greenwich mean time or 12:15 P.M. Greenwich mean time (assuming that the default settings are used). The following is a breakdown of the hierarchy status messages that are sent for the organization in this example:

• For each server:
  • One folder hierarchy status message.
  • One system folder hierarchy message.
  • One Internet newsgroup hierarchy message.
  • Five Events Config hierarchy messages.
• A total of 8 messages for each server, multiplied by 10 (for the number of servers in the organization) equals 80 total messages.

To lessen the traffic that hierarchy status messages generate in organizations:

1. Eliminate the public information store on any server that does not need one (for example, a user-only server) in any site. This immediately lessens the hierarchy status message traffic.
2. Add the Replication Send Status Timeout registry value. To do this, you must edit the registry.
   
   WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.
   
   To add the Replication Send Status Timeout value:
   1. Start Registry Editor (Regedt32.exe).
   2. Locate and click the following key in the registry:
      HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\ParametersPublic
   3. On the Edit menu, click Add Value, and then add the following registry value:
      Value name: Replication Send Status Timeout
      Data type: REG_DWORD
      Radix: Decimal
      Value data: Number of seconds; the default value is 84,600 (1 day)
      This value controls whether the current time is an appropriate time to send a status message. By default, status messages are sent once in each 24-hour period; therefore, if the last time that a status message was sent is less than 24 hours from the current time, there is no need to send a status message.
      
      CAUTION: If you increase the Replication Send Status Timeout value to more than the default value of one day, you may cause delays in the notification to servers that they are out of synchronization, and you may delay the backfill.
3. Add the Replication Send Status Alignment registry value:
   1. Locate and click the following key in the registry:
      HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\ParametersPublic
   2. On the Edit menu, click Add Value, and then add the following registry value:
      Value name: Replication Send Status Alignment
      Data type: REG_DWORD
      Radix: Decimal
      Value data: Number of seconds; the default value is 42,300 (12 hours)
      This value controls how often the status message task checks to send status messages.
4. Add the Replication Send Status Alignment Skew registry value:
   1. Locate and click the following key in the registry:
      HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\ParametersPublic
   2. On the Edit menu, click Add Value, and then add the following registry value:
      Value name: Replication Send Status Alignment Skew
      Data type: REG_DWORD
      Radix: Decimal
      Value data: Number of seconds; the default is 0 (which signifies 12:15 Greenwich mean time)
      This value is the offset that is added to the Replication Send Status Alignment value; the Replication Send Status Alignment Skew value changes the time at which the status message task runs. For example, if you want the task to run at 12:00 A.M. eastern time, set this value to 14400 (which is a four-hour offset from Greenwich mean time; a value of 14400 sets the task to run at 4:00 A.M. Greenwich mean time, which is 12:00 A.M. eastern time).
   3. Quit Registry Editor.

Public Folder hierarchy status messages are also automatically sent out when the Information Store service is started. You can also control this process (turn it on or off) by adding the Disable Replication Messages At Startup registry key:

1. Start Registry Editor (Regedt32.exe).
2. Locate and click the following key in the registry:
   HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\ParametersPublic
3. On the Edit menu, click Add Value, and then add the following registry value:
   Value name: Disable Replication Messages At Startup
   Data type: DWORD
   Radix: Binary
   Value data: 1 or 0; default value is 0
4. Quit Registry Editor.

If this registry entry is not present or is present and set to 0, public folder replication works as originally designed. In other words, public folder replication sends the replication status messages when the information store starts. If this registry entry is present and set to 1, public folder replication does not send the status messages when the information store starts.

It is also very important to differentiate between public folder hierarchy status messages and folder status messages. Folder status messages are only sent when a change is detected between the local change number and the remote change number of a folder object. If there is no change, no status message is sent for a folder object. This differs from hierarchy status messages, in that hierarchy status messages are always sent. If "Replication Outgoing Messages" is set to maximum, a typical folder status message in the Windows NT Event Viewer Application event log might look similar to the following message: NOTE: The message ID and folders will differ.