Corelan Team

#
# Powershell Script written by Peter Van Eeckhoutte
#
# Purpose : select the most optimal database for
# hosting a new mailbox in Exchange 2007
# taking into account that mailbox data should
# be spread across multiple databases as much as possible
#
# http://www.corelan.be:8800
#
#
# Load assembly
[System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms")

$Databases = Get-MailboxDatabase -status | sort-object Name
$lowestavgsize=0
$optimaldb=""

foreach ($Database in $Databases)
{
  write-host "Database : $Database"
  write-host "--------------------------------------------------------------"
  if ($Database.Mounted -eq "True")
  {
    $dbstats = Get-MailboxStatistics -database $Database
    $totaldbsize = 0
    $totalnrofmb = 0
    $avgmbsize = 0
    foreach ($dbstat in $dbstats)
    {
      $totalnrofmb++
      $totaldbsize = $totaldbsize + $dbstat.TotalItemSize.Value.ToMB()
    }
    if ($totalnrofmb -gt 0)
    {
       $avgmbsize = $totaldbsize/$totalnrofmb
    }
    $avgmbsize=[math]::round($avgmbsize, 2)
    write-host "   Total Database Size  : $totaldbsize Mb"
    write-host "   Number of mailboxes  : $totalnrofmb "
    write-host "   Average mailbox size : $avgmbsize Mb"

    if (($lowestavgsize -eq 0) -and ($optimaldb -eq ""))
    {
       $lowestavgsize = $avgmbsize
       $optimaldb = $Database
    }
    else
    {
      if ($avgmbsize -lt $lowestavgsize)
      {
         $optimaldb = $Database
         $lowestavgsize = $avgmbsize
      }
    }

   }
   else
   {
    write-host "Database : $Database : not mounted"
    write-host "--------------------------------------------------------------"
   }
   write-host ""
 }
#find optimal database
[System.Windows.Forms.MessageBox]::Show("Database :`n$optimaldb`n
      Avg mailbox size : $lowestavgsize Mb","Optimal Database")

C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe

    -PSConsoleFile "D:\Program Files\Microsoft\Exchange Server\bin\exshell.psc1" 

    -command ". 'C:\Scripts\selectoptimaldb.ps1'"