Eseutil /R what does this mode do and when would you use Eseutil /R ? The Eseutil /R mode is used when you need to perform a soft recovery of your Exchange Database/s ( Information Store ).  This mode of the tool should not be confused with the hard recovery mode Eseutil /C

What is the Difference between Hard and Soft recovery with Eseutil?

As mentioned above there are two recovery modes hard and soft recovery, the Hard recovery mode Eseutil /c is only used after performing an online restore (restore database because of corruption, or system failure; basically an online restore from media) and is used to playback to transaction log files so that you have a current database.

Normally Soft Recovery happens automatically after the Exchange Information store service starts and manual soft recovery using Eseutil /r is rarely required as it is run automatically, in fact manual soft recovery is not recommended at all with Exchange 5.5, yet there are some instances when you will need to perform a soft recovery manually, below are the scenarios where you would perform a soft recovery manually with Eseutil /r

·         Database drive that contains one of a storage groups Information Store fails

This causes the storage group and other Exchange Information stores (on other drives) to go offline (Dirty shutdown)

o   In this scenario if you intend on later restoring your missing database your can, still recover (soft recovery) the remaining Information stores with the use of  the /r mode along with the /I (Ignore) switch.

·         To perform an Out of Place Restore of an Information Store

Using the recovery mode together with the /D switch will allow you to recover an information store out of place, either to a Recovery Storage Group and would be particularly useful when you are ready to restore the missing database from the previous scenario above. The D switch basically allows you to specify an alternate locate (Other than the original) for the Exchange Database files

·         After a restore you see Event ID 494, 454, 101, 904, 903 the following description: Information Store (1352) ….. as outlined in the following Microsoft Kb Article: http://support.microsoft.com/kb/843092

The valid options and syntax for use with Eseutil /R is as follows:

Now that you have seen the options that can be used with Eseutil /R let’s look at it in action:

Suppose we had a scenario as one above where a drive failed that contained one of your storage groups databases, and this failure caused the storage group and remaining databases (located on another drive)to go offline. Now you want to get these remaining information stores back online ASAP and worry about restoring the missing database later. Figure 1 below show the Eseutil /R command and its output.

Figure 1: Eseutil Soft Recovery

The inclusion of the /D switch makes it possible to run this command against your database/s file in just about any location, it no longer needs to be in the original location. You can see how this switch can make Out of Place Restores and restores/recoveries of Recovery Storage groups possible. This feature however is only available in Exchange 2003 and above.

Before running Eseutil /R with the /I option is highly recommended that you make a backup copy of your transaction log files, especially in a scenario when you are recovering databases but you plan to use these log files in the future after you have restored the missing database file, as the use of Eseutil /r makes changes to your Transaction log files and may change them so that future recovery of your missing database files is impossible.

I highly recommend looking at the Microsoft document on running Eseutil /R:

http://technet.microsoft.com/en-us/library/aa998075.aspx

Please feel free to leave comments or questions I am always happy to answer!