Exchange Defragmentation using ESEUTIL /d Command

Exchange database defragmentation rearranges the data stored under the hard disk. It increases data accessing and retrieval speed. ESEUTIL defrag the information store and directory databases. The ESEUTIL d defragmentation mode increases the disk performance and helps to run server more smoothly and efficiently.


One can perform any from the two online and offline defragmentation Exchange. But it is mostly recommended to carry out offline defragmentation. Because ESEUTIL defrag offline shrinks size of database removing white space while ESEUTIL Online defrags is an automatic process that defrag database while keeping the actual database size same.

  • Note: run ESEutil command on one database at a time.

Caution: Perform database defragmentation during off-hours

Given Below are the switches to run on specific database

ESEUTIL /d – Exchange Database Defragmentation

Database defragmentation desires free disk space equal to 110% of the size of database. One can simplify determine the free disk space by running ESEUTIL /ms “DatabaseName.edb” at a command prompt.

Actual Process to Calculate the Free Disk Space

  1. Run command ESEUTIL /ms it will five u free space multiply it by 4KB
  2. Subtract the number you obtain from the above steps from database physical size.
  3. To obtain the resulting figure user needed for database defragmentation multiply the resultant of step 3 figure with 110%.
  4. Exchange Database Defrag time: Multiply the resultant figure by 9GB to get the approx time that defragmentation process takes.

Run ESEUTIL /D (Defragmentation)

Before you begin check the free disk space equal to 110% of the size of database and the database should be dismount.

From Exchsrvr\Bin folder, type Eseutil/d command, (a database switch)

Syntax: Eseutil /d <database_name>

Example: C:\program files\exchsrvr\bin> Eseutil /d c:\progra~1\exchsrvr\mdbdata\priv1.edb

Simple diagrammatic representation on what actually Eseutil /p command does

For Example

  1. A corrupted state of database

  2. After repairing using eseutil /p the corrupted page get replace by "white space"

  3. After Exchange Database Defragmentation

Option to specify you want to perform in Database