Restarting the BlackBerry Enterprise Server services may cause delays in message delivery

Article ID: KB04789

Type: Support Content

Last Modified: 11-10-2014


Product(s) Affected:

  • BlackBerry Enterprise Server for Microsoft Exchange
Jump to: Environment | Overview
  • BlackBerry Enterprise Server for Microsoft Exchange
  • Devices with BlackBerry Built-In software
  • Devices with BlackBerry Connect software

When restarting certain BlackBerry Enterprise Server services, BlackBerry smartphone users might experience a delay in email message delivery to their BlackBerry smartphones. The following are BlackBerry Enterprise Server services that, when restarted, might cause messaging delay:

For BlackBerry Enterprise Server 3.6

  • BlackBerry Server <server_name>, where <server_name> is the name of the BlackBerry Enterprise Server instance.

For BlackBerry Enterprise Server 4.0 to 5.0 SP3

  • BlackBerry Controller
  • BlackBerry Dispatcher

Note: For the suggested order to restart BlackBerry Enterprise Server services,  see KB13718.

The length of the delay varies depending on conditions within specific environments. Some of these conditions can include (but are not limited to) the following:

Mailboxes on the messaging and collaboration server that contain data in excess of 1 GB:

The BlackBerry Enterprise Server completes a full mailbox scan when the BlackBerry Enterprise Server services are started. Email messages are not sent to individual BlackBerry smartphone users until this scan has been completed. The scan determines if there are any items in each BlackBerry smartphone user's mailbox that need to be processed by the BlackBerry Enterprise Server. The more items in the BlackBerry smartphone user's mailbox, the longer the scan process takes.

There are many BlackBerry smartphone users on the BlackBerry Enterprise Server (for example, 300 or more):

When the BlackBerry Enterprise Server services are restarted, a full mailbox scan is completed for each BlackBerry smartphone user. These scans are run parallel to each other. The length of time it takes for the initial resource load to subside varies. The initial resource load may cause messaging delays for the BlackBerry smartphone users. In order to minimize the impact of potential messaging delays, the BlackBerry Enterprise Server services should be restarted during non-production hours unless otherwise necessary.

Messaging server performance:

The BlackBerry Enterprise Server waits for responses from requests made to the Microsoft Exchange Server. If the Microsoft Exchange Server is slow to respond to the BlackBerry Enterprise Server requests, messaging delays may occur. Other activities occurring on Exchange, including such as backups, archiving, or scanning, can cause the Microsoft Exchange Server to respond more slowly than usual.

The BlackBerry Enterprise Server services have been stopped for a long period of time:

The longer that the BlackBerry Enterprise Server services are stopped, the more pending email messages there are in the BlackBerry smartphone user's mailbox. The BlackBerry Enterprise Server has more to process when the BlackBerry Enterprise Server services start up again.

Network speed:

During a mailbox scan, the BlackBerry Enterprise Server accesses the Microsoft Exchange Server where the BlackBerry smartphone users are located. If requests sent from the BlackBerry Enterprise Server or the responses from the Microsoft Exchange Server are delayed, the time to complete the mailbox scan will also be affected.

Messaging server location:

If the messaging server is located in a different physical location from the BlackBerry Enterprise server, this can impact message delivery times. For more information on the effects of latency on a BlackBerry Enterprise Server for Microsoft Exchange, see KB14139.

Note: Mailbox scans start each time the BlackBerry Enterprise Server services are started, so repeatedly restarting the BlackBerry Enterprise Server services is not recommended.


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