Exchange Server databases consist of messages and directory information. To maintain the consistency of these databases, it uses a reliable and transactional database engine called JET. The engine has been optimized to support transaction-based processing. It implements disk caching by continually swapping pages of size 4KB between RAM and a dedicated swap space on the disk. It makes changes to the pages in memory and then writes them back to the disk. This results in improved efficiency as data is buffered in the memory itself eliminating the need to access the disk over and over again.
Caching is an effective of processing data. However, this has a downside. The data that resides on the disk is never completely up-to-date. If there are bad pages in the memory, the Exchange database may become inconsistent. Further, if the server crashes before the contents of the memory are transferred to the disk, you will lose your valuable data. To avert such disasters, MS Exchange uses transaction logging. In the event of a crash, you will be able to recover data up to the last committed transaction using transaction log files. These files keep track of all changes (i.e. inserts, deletes, and updates) made to the database and keep a copy of data processed in the memory.
Exchange databases typically experience two types of corruption, i.e. physical corruption and logical corruption. Physical corruption occurs at the lowest level and is often caused by hardware failures. On the contrary, logical corruption may happen at the database level (index entries referring to invalid or missing values) or at the application level (damaged items in mail folders, corrupt messages, etc.). Physical corruption can be detected through online backup tasks that involve checking every single page in the database. You can use the ‘Eseutil /p’ tool that comes with the Exchange Server to repair physical database corruption. Logical corruption, which is usually caused by software bugs, can be fixed using ‘Isinteg’ utility. The ‘Isinteg’ tool runs at the logical schema level and recovers data that cannot be recovered using the ‘Eseutil’ utility.
In case the MS Exchange inbuilt utilities fail to repair corruption in your database, you should take help of professional Exchange database recovery software. With the help of these tools, you can repair severely damaged databases and restore them to their original consistent state. They support recovery of Unicode-formatted Exchange database (‘.EDB’) files. Moreover, these utilities are compatible with MS Exchange 2010, 2007, 2003, 2000, and 5.5.![]()
Caching is an effective of processing data. However, this has a downside. The data that resides on the disk is never completely up-to-date. If there are bad pages in the memory, the Exchange database may become inconsistent. Further, if the server crashes before the contents of the memory are transferred to the disk, you will lose your valuable data. To avert such disasters, MS Exchange uses transaction logging. In the event of a crash, you will be able to recover data up to the last committed transaction using transaction log files. These files keep track of all changes (i.e. inserts, deletes, and updates) made to the database and keep a copy of data processed in the memory.
Exchange databases typically experience two types of corruption, i.e. physical corruption and logical corruption. Physical corruption occurs at the lowest level and is often caused by hardware failures. On the contrary, logical corruption may happen at the database level (index entries referring to invalid or missing values) or at the application level (damaged items in mail folders, corrupt messages, etc.). Physical corruption can be detected through online backup tasks that involve checking every single page in the database. You can use the ‘Eseutil /p’ tool that comes with the Exchange Server to repair physical database corruption. Logical corruption, which is usually caused by software bugs, can be fixed using ‘Isinteg’ utility. The ‘Isinteg’ tool runs at the logical schema level and recovers data that cannot be recovered using the ‘Eseutil’ utility.
In case the MS Exchange inbuilt utilities fail to repair corruption in your database, you should take help of professional Exchange database recovery software. With the help of these tools, you can repair severely damaged databases and restore them to their original consistent state. They support recovery of Unicode-formatted Exchange database (‘.EDB’) files. Moreover, these utilities are compatible with MS Exchange 2010, 2007, 2003, 2000, and 5.5.
