Resolve Logical Corruption To Resolve Inaccessibility In Edb Database

By Author: Tom Robinson
Total Articles: 2
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MS Exchange Server is the reliable messaging system that is broadly utilized in organizations, businesses, workplaces and homes. It consists of batch of EDB files that contain the whole database of Exchange Server. Any kind of physical or logical corruption can cause issue of severe data loss which can certainly obstruct the smooth flow of business operations around an organization. Logical corruption can make the entire database files inaccessible which can be averted by some methods which identify and correct common problems caused by logical corruption. Following cases are the possible causes of logical corruption in MS Exchange Server.

Deleting Edb.log

In the Exchange Server database log file, there are some records that may contain some changes that have been incurred to the original database. If the log file (Edb.log) is deleted, it may create a partially- committed transaction which may result in minor problem such as partially moved message. It may also give birth to major logical problem in the database or cause severe internal inconsistency in one or more B- trees.

Write-Back Caching

Logical ...
... corruption may also occur if you run an unprotected write- back cache against the log drive. An unprotected write- back cache is a cache which is volatile and loses data with sudden interruption in the electricity. When a write operation to the log disk is completed, Extensible Storage Engine 98 (ESE 98) commits the transaction and makes the data available on the disk. Any durable updates prevail in the log disk even if the computer stops functioning immediately after the transaction is committed. After the data is written to the log disk, ESE 98 gets ready to automate the corresponding page to the database disk. If the data was never written to the log disk, the database cannot retrieve the data further and it stays corrupted.
To lower down the potential of problem you must make sure that the data in the cache is totally protected with a battery backup, with error checking, error correction and sound operational procedure.

Repairing by using Eseutil /p

Another prominent cause for logical corruption in EDB database could be the use of eseutil /p command. When there is data loss and inefficient space usage in the database, you must run an offline defragmentation (eseutil /d) to resolve the issue of wasted space and inefficient space usage. After executing the offline defragmentation process, you must execute an integrity check (Isinteg -fix) process to resolve any store level logical corruption that the previous process might have incurred. In addition, if the space tree restricts further insertion of new records into the table, any typical transaction operations that are performed against the database may fail. Therefore, you should execute defragmentation before you run an integrity check.

Whatever be the reason, any case of logical corruption causes data inaccessibility and makes the database unusable. To fight with such issues, MS Exchange recovery tool is used to restore Exchange. Kernel for Exchange Server Recovery is such a Microsoft Exchange recovery utility that repairs whole Exchange database by recovering private as well as public folders of Exchange Server.