Error: Database size has exceeded the size limit of
Product:
Microsoft Exchange Server
Error Message: [Event
ID 9690]
Exchange store '<storage group
name>': The logical size of this database (the logical size equals the
physical size of the .edb file and the .stm file minus the logical free space
in each) is <number> GB. This database size has exceeded the size limit
of <number> GB.This database will be dismounted
immediately.
Problem Cause
The above error message comes when the logical size of the
database becomes greater than the one that you configured.
The logical size of the database is calculated by adding the
physical size of EDB and STM files minus the logical free space in them.
Default Size Limit of
Exchange Server
Exchange Server 2003
Database Size Limit
In Microsoft Exchange 2003,
Standard Edition supported two databases in single storage group (one for
mailbox and other for public folder database). The standard edition before SP2
of Exchange Server 2003 have 16 GB database size limit for each database which
cannot be configured further. However with SP2 Edition you get 18 GB default
configuration limit which is 2GB extra with a maximum size limit of 75 GB,
which means you can increase the limit by upto 75 GB by using a registry key.
The enterprise edition of Exchange Server 2003 gives 8,000
GB (actually it depends on the hardware of the system) size limit for each
database.
Database Size Limit
in Exchange Server 2007 and later version (2010 and 2013).
Exchange Server 2007 standard
edition RTM supported five databases and up to five storage group (instead of
just two databases which is the case of in Exchange Server 2003 edition). The
default size limit is 50GB per database which can be increase up to 15 TB by
editing registry values. In Exchange 2007 Standard Edition SP1 the limit is
250GB. There is no default database size limit for the Exchange 2007 Enterprise
Edition.
In standard edition of Exchange Server 2010 the default size
limit is 1024 GB (i.e 1 TB) and there is no default size limit for Enterprise
edition users.
In Exchange Server 2013 we got maximum limit of 16TB although
it recommended to use 2 TB size limit for database because the larger the size
of Database, larger the time taken to take backup and recovery process.
What will
happen if the configured or licensed database size limit reached?
As soon as the database mounts in Exchange
Server the following process will happen
- The
store process compares the Physical Database size with the Configured
Database Size Limit.If the physical size is within or exceeds the
configured Database Size Warning Buffer in Percentage, the store
performs a logical calculation of the database size.
- If it is below this warning buffer, there is no
need to calculate the free space because the logical size will never exceed the
physical size.
With Exchange Server 2003 SP2 or later, the server performs
the following tasks when the configurable (or default configured) database size
limit is reached:
- If the first check after a database mount finds
the database size above the limit, the database will not be taken offline but
an error event (ID 9689) will be logged in the Application event log.
- If it is the second check, an error event will
be logged in the Application event log and the database will be taken offline.
So what’s the solution to the
problem stated above? Offline Defragmentation! No, you will need at least 1.5
times the database size in available hard drive space to run it. Below are the
best possible solutions for the problem of Database size exceeded size limit.
Solution
Method 1: Increase
the configured size limit of Exchange Database using Registry
Note: Incorrectly
editing the registry can cause serious problems that may require you to
reinstall your operating system.
Step 1: Open
Regedit and browse to the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\<Server
Name>\Private-<database GUID>
Step 2: If the key “Database Size Limit in GB” DWORD already
exists under the subkey “Private-[database GUID]”, change its
value to the desired size in gigabytes, be sure to select ‘decimal’ when you
enter the number.
If the “Database Size Limit in
GB” DWORD does not exist for the subkey then create a new DWORD “Database Size
Limit in GB”, and then set its decimal value to the desired size in gigabytes.
Note: You may need to restart the information
store service for the changes to take effect.
Step 3: Restart the Microsoft Exchange Information Store service
Step 4: Check
event viewer for the following events:
Event ID 1216 will provide
information about what is the current physical size of the database and how
much size is allocated.
Method 2: Reduce
the size of database or create a new database.
You can reduce the database size
by creating a new database and move the files into it. Or you can ask users to
delete mailbox or public folder data that is not required. But deleting mails
will not create free space most of the time and it is better to create a new
database and move some data into it. Moving mailboxes from one Exchange
Database to another cleans corrupt items and will boost the performance. After
moving the database makes sure you update your backup scheme to include the
newly created second database. One more benefit of creating a new database is it
allows you to keep your store up and the mail flows.
What if the problem still exists?
What if the above two solutions
failed to work and you still get the error “This database will be dismounted
immediately.” So it is recommended to convert the edb files of the Exchange
Server into PST file which can done by EDB to PST Converter easily even if
there is size, corruption or dismounting database issues.
By converting EDB file (priv.edb
and pub.edb) into PST file format user can get rid of the problem of edb size
and dismounting issues.