Q255035: XADM: Recovering Hard Drive Space from Exchange Server Databases
Article: Q255035
Product(s): Microsoft Exchange
Version(s): 5.5
Operating System(s):
Keyword(s): exc55
Last Modified: 06-AUG-2002
-------------------------------------------------------------------------------
The information in this article applies to:
- Microsoft Exchange Server, version 5.5
-------------------------------------------------------------------------------
SUMMARY
=======
This article describes how to free hard disk space from Exchange Server
databases if there is insufficient free disk space to carry out an offline
defragmentation.
The Eseutil utility can perform an offline defragmentation, which releases unused
hard drive space from Exchange Server databases to the file system. Eseutil
requires free hard disk space equal to at least 110 percent of the database size
(to create a temporary database that is used in the defragmentation).
If no local drive has sufficient space for an offline defragmentation, you can
use one of the three following options, which are expanded on in the "More
Information" section of this article:
- Offline defragmentation with redirected temporary database. Redirect the
temporary database to another logical drive, such as a mapped network drive
or a temporarily installed hard disk.
- Moving information to another server and recreating empty databases. Move all
of the information that either one or both of the information store databases
contain to another server. Stop the service, delete the databases, and then
restart the service to recreate empty databases.
- Offline defragmentation on another computer. Move the database files to
another computer, and then perform the offline defragmentation on that
computer.
MORE INFORMATION
================
Eseutil is a part of the Exchange Server 5.5 installation and is located in the
Winnt\System32 folder. Eseutil can perform an offline defragmentation, which
releases unused hard disk space from Exchange Server databases to the file
system. Online defragmentation, which the information store runs during the
scheduled online information store maintenance period, does not release disk
space to the file system. The amount of space that Eseutil releases is
approximately equal to the amount of unused space in the databases. For
additional information about how to determine free space in the Exchange Server
databases, click the article number below to view the article in the Microsoft
Knowledge Base:
Q195914 XADM: Determining Database Free Space with Exchange 5.5 SP1
Offline defragmentation requires free hard disk space of at least 110 percent of
the database size. For example, Eseutil requires up to 1.10 gigabytes (GB) of
free space to defragment a 1-GB Priv.edb database. Eseutil uses this hard disk
space to create a temporary database that the defragmentation process uses. By
default, Eseutil creates this database in the current working folder of the
command prompt session from which Eseutil runs. For additional information about
Eseutil free disk space requirements, click the article number below to view the
article in the Microsoft Knowledge Base:
Q183888 XADM: Free Disk Space Requirements for Eseutil.exe
Offline Defragmentation with Redirected Temporary Database
----------------------------------------------------------
You can use free space on another local or network drive by specifying the path
and file name for the temporary database. The specified path must be on a
lettered drive, not in a Universal Naming Convention (UNC) path. For example,
C:\<path_name_1>\<path_name_2>\Tmpdfrg.edb is acceptable, but
\\<file_server>\<sharepoint>\tmpdfrg.edb is not allowed.
You can add a temporary physical drive to the server specifically for
defragmentation. You can also map a network drive by using the net use command.
The following sample command specifies the temporary database path and file name
G:\Folder1\TempDfrg.edb:
eseutil /d /ispriv /tG:\Folder1\TempDfrg.edb
Notice that there is no space between the /t and the drive letter.
Moving Information to Another Server and Recreating Empty Databases
-------------------------------------------------------------------
WARNING: Before you perform the following procedure, back up all Exchange Server
databases and verify the databases' integrity. If you do not back up your
databases, you may permanently damage or lose your databases.
You can move all of the information from an information store database to another
server and then recreate an empty database in the information store database's
place to effectively free disk space. If the information store does not find a
database where a database should exist, the information store service recreates
an empty database.
To move information to another server and recreate empty databases:
1. Use one of the following procedures, as applicable, to move the database
information to another computer:
- Private information store. To move information from the private
information store (Exchsrvr\Mdbdata\Priv.edb), use the Move Mailbox
utility from the Exchange Server Administrator program to move all of the
user mailboxes to another Exchange Server computer. You must move hidden
user mailboxes as well. Do not move system mailboxes, such as mailboxes of
the Internet Mail Service or directory service; the system services
recreate the system mailboxes in the empty database during startup.
- Public information store. To move information from the public information
store (Exchsrvr\Mdbdata\Pub.edb):
a. Make sure that there is at least one replica of every public folder on
the server. Open the public folder properties, click the Properties
tab, and then make sure that at least one other server is listed in the
"Replicate folders to" list.
b. Verify that public folder replication is complete. Open the public
folder properties, click the Folder Replication Status tab, and then
make sure that replication is complete.
c. Delete the original public folders. You can also move public folders to
another site.
For additional information, click the article number about how to move public
folders to another site below to view the article about how to move public
folders to another site in the Microsoft Knowledge Base:
Q154947 XADM: How to Move a Public Folder to Another Site
2. Stop the information store service, delete the database for which you moved
information to another server, and then restart the information store
service. The information store recreates empty databases.
3. Restore the information that you moved to another server.
After you perform these steps, any free space in the database is returned to the
file system's available space.
Offline Defragmentation on Another Computer
-------------------------------------------
You can also move the databases to another computer that Microsoft Exchange
Server is not installed on and run Eseutil on that computer. For additional
information, click the article number below to view the article in the Microsoft
Knowledge Base:
Q244525 XADM: How to Run Eseutil on a Computer Without Exchange Server
Quick Reference
---------------
The following outline provides a quick reference of the options that are
available to free hard disk space from Exchange Server databases.
- Offline defragmentation with temporary database redirected
- Current drive
- Another drive temporarily added to system
- Over network
- Move the database to another computer
- Move all information to another server and delete to start over with empty
database
- Private information store. Move mailbox
- Public information store. Remove all instances, and so on
- Move database to another computer and perform offline defragmentation on that
computer
- Q244525 - XADM: How to Run Eseutil on a Computer Without Exchange Server
- Public information store. Remove all instances, and so on
Additional query words: edbutil defrag OLD
======================================================================
Keywords : exc55
Technology : kbExchangeSearch kbExchange550 kbZNotKeyword2
Version : :5.5
Issue type : kbhowto
=============================================================================
THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.
Copyright Microsoft Corporation 1986-2002.