I am not sure if this is a good place to post stuff like this, but I don't have a blog so I figured this was better than hording the code. If there is a better place that is still Exchange centric, please let me know and I will start using it instead (I just don't want to set up a blog or anything like that). A note about the script - it started off as a copy of a script that Peter Van Eeckhoutte. We quickly realized though that in our enviornment, the best location to place new mailboxes was not on the database with the smalles amount of data, but rather on the database with the least number of active mailboxes on it so we modified the scripts selection criteria. We also use the DataTable sorting capabilities versus some of the math and loops Peter used in his original script. Lastly we always run these script in the EMS, so we don't normally include the Exchange snap-in, so you would need to do this if you ran this script as a part of some automated process. Since we have 100 databases, this data can be a bit much to collect every time a new mailbox is added, so we keep it as a separate script and run it a couple of times a day just to update ourselves as to the most "optimal" database. Hopefully this helps people out there running Exchange 2007. # # Powershell Script originally written by Peter Van Eeckhoutte - but heavily modified since then. # http://www.corelan.be:8800/index.php/2009/01/19/exchange-2007-powershell-script-to-select-optimal-database-for-a-new-mailbox/ # # This script selects the most optimal database for hosting a new mailbox in Exchange 2007, taking into account the number of active mailboxes # in the database. I.E. It doesn't consider the amount of disconnected mailboxes as they will soon be purged. # # Create a DataTable to host the mailbox data. $MBXDBTable = New-Object system.Data.DataTable “MBXDatabaseTable” # Create the columns by defining their name and attribute type. $MBXDBTable.Columns.Add("DataBaseName",[String]) | Out-Null $MBXDBTable.Columns.Add("ActiveMBs",[Int]) | Out-Null $MBXDBTable.Columns.Add("InactiveMBs",[Int]) | Out-Null $MBXDBTable.Columns.Add("TotalMBs",[Int]) | Out-Null $MBXDBTable.Columns.Add("TotalMBSize",[Decimal]) | Out-Null $MBXDBTable.Columns.Add("AverageMBSize",[Decimal]) | Out-Null # Query just the mailbox databases with "MBX*" in the name, which avoids other server with a mailbox database, and skip any recovery databases. $Databases = Get-MailboxDatabase -status | where {$_.Name -like "MBX*" -and $_.Recovery -eq $False} | sort-object Name # Set the loop count to 0. $LoopCount=0 # Loop through each database in the above query. Foreach ($Database in $Databases) { # Check to see if the database is mounted, otherwise skip to down below. if ($Database.Mounted -eq "True") { # Define the query which specifies grabbing statistics for each mailbox in the database. # NOTE: This only grabs information on mailboxes that have been created in the database. New mailboxes that haven't been "created" will not show up here. $DBStats = Get-MailboxStatistics -database $Database # Set the initial values to 0 for each database being processed. $TotalActiveMB = 0 $TotalInactiveMB = 0 $TotalNrofMB = 0 $TotalDBSize = 0 $AvgMBSize = 0 # Loop through the statistics for each mailbox in the database. foreach ($DBStat in $DBStats) { # Count the total number of mailboxes (active and inactive). $TotalNrofMB++ # Add the size of the mailbox to the total size of all mailboxes in the database. $TotalDBSize = $TotalDBSize + $DBStat.TotalItemSize.Value.ToMB() # Count the number of mailboxes that are not disconnected (I.E. they are still active). If ($DBStat.DisconnectDate -eq $Null) { $TotalActiveMB++ } } if ($TotalNrofMB -gt 0) { # Set the average mailbox size to collective mailbox size divided by the number of mailboxes. $AvgMBSize = $TotalDBSize/$TotalNrofMB # Calculate the number of inactive mailboxes by subtracting the active mailboxes. $TotalInactiveMB = ($TotalNrofMB - $TotalActiveMB) # Round out the average mailbox size. $AvgMBSize=[math]::round($AvgMBSize, 2) } # Add the gathered information to a new row in the table. $NewDBRow = $MBXDBTable.NewRow() $NewDBRow.DataBaseName = $Database.Name $NewDBRow.ActiveMBs = $TotalActiveMB $NewDBRow.InactiveMBs = $TotalInactiveMB $NewDBRow.TotalMBs = $TotalNrofMB $NewDBRow.TotalMBSize = $TotalDBSize $NewDBRow.AverageMBSize = $AvgMBSize $MBXDBTable.Rows.Add($NewDBRow) } else { # If a database is not mounted, write its name to the screen in RED text. write-host -Fore Red "Database : $Database : not mounted" } # Show a status bar for progress while data is collected. $PercentComplete = [Math]::Round($LoopCount++ / $Databases.Count * 100) $CurrentDB = $Database.Name Write-Progress -Activity "Mailbox Database Query in Progress" -PercentComplete $PercentComplete -Status "$PercentComplete% Complete" -CurrentOperation "Current Database: $CurrentDB" } # Choose the optimal database by the choosing one with the fewest active mailboxes. $Optimaldb = ($MBXDBTable | Sort-Object ActiveMBs | select -first 1) # Dump the table to the screen. $MBXDBTable | Sort-Object -Descending ActiveMBs | Format-Table -AutoSize # Dump the table to a CSV - not currently used. # $MBXDBTable | Export-CSV MailboxDBSizes.csv write-host -fore yellow "The optimal new mailbox database is" $Optimaldb.DataBaseName "based upon the active mailbox count of" $Optimaldb.ActiveMBs "`b."