There is a fantastic script on Kurtdepauw’s blog (http://kurtdepauw.wordpress.com/2007/11/10/dbbalancer-load-balance-your-exchange-mailbox-databases/) to assist in evenly balancing your Exchange 2007 databases so they are of similar size.

I have customized it slightly and highlight the 2 lines below as useful modifications:

Line 78 – added ‘| Where-Object {$_.Name -notlike “Archive Storage Group”}’ – this is very useful if you want to exclude certain databases from being touched by the balancing script

$DBs = Get-MailboxDatabase -Server $Global:hshParameters.MailboxServer | Where-Object {$_.Name -notlike "Archive Storage Group"}

Line 130 – added -PreserveMailboxSizeLimit switch – you will need to add this so that you can move mailboxes that exceed the database default limits

Move-Mailbox -Identity $Mailboxes[$intRandomMailbox] -TargetDatabase $Global:strSmallestDB.Split(";")[0] -PreserveMailboxSizeLimit -Confirm:$false

———-

Update 04/11/2009

I’ve been alerted that the link to Kurtdepauw’s blogis broken. I’ve posted the entire code below:

# DBBalancer Version 1.1
# Written by BoerLowie (sammybog@gmail.com)
# Modified by www.danovich.com.au - 12/03/2009 - www.danovich.com.au
#
# This script is used to maintain a balance between your different Exchange 2007 Mailbox Databases
#
# Configuration/Installation
# --------------------------
#
# To install the application, just place the script and the config file in C:\Program Files\DBBalancer
#
# The configuration is stored in DBBalancer.xml  Use the line below as a reference XML Config file (just paste it in notepad and save it as DBBalancer.xml
#
# <Objs Version="1.1" xmlns="http://schemas.microsoft.com/powershell/2004/04"><Obj RefId="RefId-0"><TN RefId="RefId-0"><T>Deserialized.System.Collections.Hashtable</T><T>Deserialized.System.Object</T></TN><DCT><En><S N="Key">ThresholdInGB</S><I32 N="Value">5</I32></En><En><S N="Key">MailboxServer</S><S N="Value">S-BE-KI-EX</S></En></DCT></Obj></Objs>
#
# You can run the script in foreground or schedule it.  To schedule it, create a task using the following command line:
#
# PowerShell.exe -PSConsoleFile "C:\Program Files\Microsoft\Exchange Server\Bin\exshell.psc1" -Command "C:\DBBalancer\DBBalancer.ps1"
#
# Make sure your account is at least an Exchange Server Administrator on the Mailbox Server.
#
# The following values are used in the xml file:
#  - ThresholdInGB:  The script will start to balance you databases if the difference between the biggest
#                    DB and the smallest DB exceeds this value.  This should be set to something like 5 GB.
#  - MailboxServer:  The MailboxServer to balance.  The script can be run from every machine with Exchange 2007 Management Tools
#                    installed on, so it needs to know which Mailbox Server it needs to connect to.  The script will balance all DB's on this
#                    mailbox server.
#
# Processing
# ----------
#
# The script will move a RANDOM mailbox from the Biggest DB to the Smallest DB until all DB are within the Threshold limit.  So if you
# set the Threshold to 5 GB, all DB's will be equally loaded with a maximum difference of 5 GB.
# Only one mailbox at a time will be moved to minimize user downtime.
#
# Logging
# -------
#
# You can follow the progress of the script in the Application Log.  Look for events of Source DBBalancer.
# Every mailbox move will be listed in the eventviewer.
#
# When all Mailbox Databases are balanced, the following will be displayed in the Event Viewer:
#  All Mailbox databases are balanced within the Threshold limit.

Start-Init
If (Check-Prerequisites -eq $true)
{
If (Do-MainLoop -eq $True)
{
$Global:objEventLog.WriteEntry("All Mailbox databases are balanced within the Threshold limit.")
}
}
Else
{
$Global:objEventLog.WriteEntry("Prerequisites check failed.  You probably have only 1 Mailbox Database and therefor we can't move mailboxes around.")
}

This PowerShell script queries the defined Exchange 2007 server and emails in HTML format the top 25 biggest mailboxes to the defined receipents. Simply create a scheduled task and you can have a automated weekly report:


# Name: top25.ps1
# Purpose: Report on the 25 largest mailboxes on an Exchange server and email this report in HTML format

# Set the Exchange server to run the query against

$ExchangeServer = “EXCHANGESERVERNAME”

# Run the query

$Top25Users = Get-MailboxStatistics -server $ExchangeServer |sort-object -Property totalitemsize -des |select-object Displayname, ItemCount, @{name=’Total Item Size (MB)’;expression={$_.totalitemsize/1MB}} -first 25 |Convertto-html

# Set the mail message properties

$FromAddress = “FROM@DOMAIN.COM.AU”
$ToAddress = “TO@DOMAIN.COM.AU”
$MessageSubject = “Weekly report: Top 25 biggest mailboxes on Exchange server ” + $ExchangeServer
$SMTPServer = “SMTPSERVER.DOMAIN.COM.AU”

# Create the mail message

$SMTPMessage = New-Object System.Net.Mail.MailMessage $FromAddress, $ToAddress, $MessageSubject, $Top25Users
$SMTPMessage.IsBodyHtml = $true

# Send the message

$SMTPClient = New-Object System.Net.Mail.SMTPClient $SMTPServer
$SMTPClient.Send($SMTPMessage)

To run a Exchange 2007 Powershell script as a scheduled task you need to call the Exchange Shell as part of the command eg:

powershell -psconsolefile "C:\Program Files\Microsoft\Exchange Server\bin\exshell.psc1" -command "& 'your script.ps1' "

Powershell and Exchange 2007 allow for setting user mailbox limits (including warning and send / receive restrictions) based on Active Directory Group Membership.

For example, you can create a Powershell script that sets a 1GB mailbox limit for all users in the ‘Exchange Mailbox 1GB Storage Limit’ Active Directory Group.  Schedule this script to automatically run overnight and you no longer need to move users between mailstores or manually set limits in the account properties. Code below:

Whilst recently installing the Hub Transport role of Exchange 2007 SP1, the installation failed because it could not start the OpsMan server (it was disabled, another story). After enabling the service I went to reinstall the role and had the error shown below, indicated that I needed to perform the “BuildToBuildUpgrade” action.

After checking out the Exchange Team Blog (http://msexchangeteam.com/archive/2007/05/21/439529.aspx) it looked like I needed to remove a registry key.

Delete Watermark

Delete the Watermark key and restart your Exchange installation. For me, the Hub Transport role had successfully installed, it just looked like the installation said it had failed after unsuccessfully trying to start the OpsMgr services as one of the last tasks in the installation.

After a reasonably painless recent rollout of SEP v11 to our fleet, we’ve come across some issues running it on a Windows 2003 Active-Passive Exchange 2003 cluster. Symptoms: nodes unresponsive, sometimes together, sometimes minutes after the other one – not even blue screened but completely unresponsive, nothing on the console.

Anyway the short of it was that we managed to get a memory dump and learned that system32\drivers\wpsdrvnt.sys had been causing the issues. Doesn’t ring a bell? Well it’s the Sygate Personal Firewall which has now been rolled into Symantec Endpoint Protection, the network threat protection component.

We obviously didn’t want to completely remove AV from our email system if possible, so we modified the installation to only contain the core files plus AV protection (see below)

2 weeks running like this and the problem has not reoccurred.