Online database maintenance is configured

[This topic is intended to address a specific issue called out by the Exchange Server Analyzer Tool. You should apply it only to systems that have had the Exchange Server Analyzer Tool run against them and are experiencing that specific issue. The Exchange Server Analyzer Tool, available as a free download, remotely collects configuration data from each server in the topology and automatically analyzes the data. The resulting report details important configuration issues, potential problems, and nondefault product settings. By following these recommendations, you can achieve better performance, scalability, reliability, and uptime. For more information about the tool or to download the latest versions, see "Microsoft Exchange Analyzers" at https://go.microsoft.com/fwlink/?linkid=34707.]  

Topic Last Modified: 2009-03-12

The Microsoft Exchange Analyzer Tool examines the Windows registry to determine whether one or more of the following registry entries are set:

  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\ParametersSystem

    Value name: Online Maintenance Checksum

    Value type: REG_DWORD

  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\ParametersSystem

    Value name: Zero Database Pages During Checksum

    Value type: REG_DWORD

  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\ParametersSystem

    Value name: Throttle Checksum

    Value type: REG_DWORD

By default, these registry entries are not set on a computer that is running Microsoft Exchange Server 2007. If one or more of these registry entries are set, Exchange Analyzer generates one or more of the following messages.

If Online Maintenance Checksum is set

Online maintenance database checksum is enabled on server <ServerName>. Please visit Online Maintenance Database Scanning in Exchange 2007 SP1 (https://go.microsoft.com/fwlink/?linkid=103803) for more information.

If Zero Database Pages During Checksum is set

Online maintenance database page zeroing is enabled on server <ServerName>. Please visit Online Maintenance Database Scanning in Exchange 2007 SP1 (https://go.microsoft.com/fwlink/?linkid=103803) for more information.

If Throttle Checksum is set

Online maintenance database throttle checksum is set to <Value> on server <ServerName>. Please visit Online Maintenance Database Scanning in Exchange 2007 SP1 (https://go.microsoft.com/fwlink/?linkid=103803) for more information.

The Exchange online maintenance database checksum functionality and page zeroing functionality affect the I/O performance of the server. Therefore, if you use these features, we recommend that you read the configuration information that is mentioned in "Online Maintenance Database Scanning in Exchange 2007 SP1" (https://go.microsoft.com/fwlink/?linkid=103803).

For More Information

For more information about online maintenance database scanning, see the following topics: