Microsoft KB Archive/315196

= XADM: Automatically Purging Log Files Without Online Backup =

PSS ID Number: 315196

Article Last Modified on 9/19/2003

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The information in this article applies to:


 * Microsoft Exchange 2000 Server
 * Microsoft Exchange Server 5.5

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This article was previously published under Q315196



SUMMARY
This article describes a relatively easy and quick way to recover disk space when transaction logs have filled a drive and free space becomes an issue for uninterrupted operation of the Exchange 2000 or Exchange Server 5.5 computer.

WARNING: This article contains information about deleting the transaction log files. In a worst-case disaster scenario, you may not be able to recover all of your data without the log files if the database becomes corrupted. Transaction log files provide a high level of recoverability, and therefore, only perform the procedure discussed in this article as a last resort in emergency situations if you cannot complete a full backup, which permanently deletes the committed logs automatically after backing them up.



MORE INFORMATION
If circular logging is disabled on your Exchange 2000 or Exchange Server 5.5 computer, after heavy operations in the information store, hundreds or even thousands of transaction logs can be created before you can perform a full backup. This may reduce disk space on the server.

To work around this situation and avoid having to manually find safe logs to delete by using Exchange database utilities, you can enable circular logging, and then restart the Information Store service. Exchange automatically deletes all the committed log files as soon as a new transaction log is created.

This procedure may cause a delay on some idle systems until the current Edbxx.log file of the relevant storage group (or the Edb.log file in Exchange Server 5.5) gets full and needs to be renamed. To speed up new log file creation and the automatic deletion process, you can send yourself an e-mail message with a 5-megabyte (MB) attachment.

Because circular logging is disabled by default in Exchange 2000 (it is enabled by default in Exchange Server 5.5), it is highly recommended that you use different partitions for the database files and the transaction logs to help prevent issues with disk space. Transaction logs and the information store database together provide a high level of recoverability when a disaster occurs; therefore, you must consider all consequences before you delete the transaction logs from the system.

For additional information about how the Exchange logging mechanism works and how to change it, click the article numbers below to view the articles in the Microsoft Knowledge Base:

147524 XADM: How Circular Logging Affects the Use of Transaction Logs

258470 XADM: How to Modify the Circular Logging Setting

Additional query words: circular logging full backup ESE

Keywords: kbhowto KB315196

Technology: kbExchange2000Search kbExchange2000Serv kbExchange2000ServSearch kbExchange550 kbExchangeSearch kbZNotKeyword2

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