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View Performance data in a web browser

Posted by Jean Louw

This is a little trick, which I have been meaning to share for a while. It is a very simple way to view performance data for your server, using a web browser. Now I am sure that it’s not news to everyone, but for those of you who see this for the first time, I am sure you’ll be able to use this in your environment.

Because I work primarily with Exchange server, I will be using some Exchange performance data for this post. However, you can use any performance counters you require, according to my knowledge they all work the same way.
To setup a basic html page with some performance data, open performance monitor, and add a counter from a remote server. I my case I have selected the % Processor Time. Once the graph starts populating with data, right-click anywhere on the graph and select “Save As”. Save the html file, either to your web server, or anywhere on your disk.
If you open the file from the disk, you have to manually start the logging again, I have noticed that if the page is loaded from a web server this is not required.

Microsoft included a very nice performance template in the Exchange 2007 Toolbox. I think we’ll start there, and open a performance counter with some pre-loaded information. You can access the performance data from the Exchange Management Console. Click the Toolbox and select Performance Monitor.
You can now save this data to an html document as before. There is one catch though, the performance data saved from this console points to the local machine. You have to open the html document in a text editor, and do a find and replace on the following string VALUE="\ with VALUE="\\MACHINENAME\ where MACHINENAME is your server name.
Now you should be able to load this html document from any computer or web server and have the selected performance data available.

Filed under: html, perfmon, tips, web No Comments

Bulk export calendars from Exchange mailboxes

Posted by Jean Louw

I have never really had the need for a script like this, so when our catering manager at the office logged a support call, requesting an export of all calendars for all of our meeting rooms, I had to investigate the possibilities. He basically needed this information in order to determine how busy the individual meeting rooms were during the last year.
Following a quick, unsuccessful, Internet probing for tools or scripts that could do this, my initial feeling was to say “No sorry, can’t be done, or if we do it, it was going to be a manual task.”
A manual task, which involves, granting access to the room mailbox, logging onto the mailbox using Outlook, and exporting the calendar data to Excel. Sounds easy, but doing that a hundred times is very unproductive and torturous to say the least.

I decided to attempt to script it, and the result is something I am both proud of and ashamed of at the same time, as I am convinced there must be a better way.

It’s a very rough method, which involves the following process:

  • Get a list of rooms from a text file (as it was emailed to me). You could use get-mailbox instead.
  • Add-mailbox permission to the current user
  • Create an Outlook profile
  • Logon to the profile
  • Export the Calendar to CSV
  • Remove-MailboxPermission

I could automate most of the above, but creating new profiles on demand is something I’ve never had to do, and frankly, I had no idea how to get around this problem. After speaking to some of the developers at work, who promised me some dotnet code which could do it (which I am still waiting for might I add :)), I decided to use PRF files.

I have used PRF files very successfully in the past, on Terminal server deployments to automatically setup Outlook profiles.

I downloaded the ORK and created a PRF which I used as a template for the script. The blank PRF is attached to this post to save you the time and effort of using ORK.

The script finds and replaces the UserName and HomeServer in the PRF, although any Exchange server should resolve you to your mailbox server. It then creates a PRF and starts Outlook with the /importPRF switch. Some extra information, for anyone wanting to actually deploy or use the PRF file; the %HomeServer% variable in the PRF does not work the same way %UserName% works, if you want use the PRF, you need to specify one of your mailbox servers instead.

While Outlook is open on that profile, the script attaches to Outlook using a COM object and downloads the calendar for the specified date.

The calendar fields can be customised to suit your needs. In my case we simply needed the Start and End date, the duration, and the Organizer.

The export data is saved and the PRF is removed, sadly the swarm of profiles will remain, and you have to manually remove them. You could remove them from HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows Messaging Subsystem\Profiles but I have not added that to the script.

I hope this can help you, if you ever get a freaky request like this.

The script and the PRF template can be downloaded from here:


Collecting Exchange database white space from the event log using .NET

Posted by Jean Louw

A recent comment from a reader, prompted me to do some updates and bug fixes to my Exchange 2007 audit script. As a part of this process, I decided to add the white space count into the mailbox store check.

I discovered an extremely helpful post, as usual, from Shay Levy, which pointed me in the right direction.

Although this function does get exactly what I needed, I did however want to search for the white space by mailbox store name, in order to get the value, as each mailbox store was passed during the script processing.

I changed my script to use .NET instead of WMI for event logs so I decided to continue using this method for the white space as well.
The basic script to collect the white space sizes from the event log using .NET is as follows:

$now = Get-Date
$colMailboxStores = Get-MailboxDatabase -Server SERVER -Status | Sort-Object Name
$spaceLog=[System.Diagnostics.EventLog]::GetEventLogs('SERVER') | where {($_.LogDisplayName -eq "Application")}

foreach ($objMailboxStore in $colMailboxStores)
Write-Host "..Getting database white space for" $objMailboxStore.Name
$store = @{Name="store";Expression={$_.ReplacementStrings[1]}}
$freeMB = @{Name="freeMB";Expression={[int]$_.ReplacementStrings[0]}}
$whiteSpace = @()
$whiteSpace += $spaceLog.entries | where {($_.TimeWritten -ge $now.AddDays(-1))} | where {($_.EventID -eq "1221")} | where {($_.ReplacementStrings[1] -match $objMailboxStore.Name)} | select $store,$freeMB -last 1

This method is very slow, as it has to dredge through the entire event log for every database. It’s really not a problem if you have a small number of databases, but in a large environment like ours, with multiple mailbox servers, this could take ages to complete.

It was was painful during testing to wait for the above script to complete and I really felt that the speed of this process should be increased, so instead I came up with the following solution:

$now = Get-Date
$spaceLog=[System.Diagnostics.EventLog]::GetEventLogs('SERVER') | where {($_.LogDisplayName -eq "Application")}
$db = @{Name="database";Expression={$_.ReplacementStrings[1]}}
$freeMB = @{Name="MB";Expression={[int]$_.ReplacementStrings[0]}}
$whiteSpace = $spaceLog.entries | where {($_.TimeWritten -ge $now.AddDays(-1))} | where {($_.EventID -eq "1221")} | select $db,$freeMB

($whitespace | where {$_.database -match $objMailboxStore.Name} | select -last 1).mb

The code above will collect all of the Event ID 1221’s for the last day and store them in a variable with the customised place holders from the expressions.
This happens once per server only and any subsequent searches can be performed against the variable instead.

The select statement at the end, also selects the last item in the list to ensure that you also look at the latest event for each database. This literally reduces the runtime of the script by a factor equal to the amount of databases on your server.

I will be posting an update to the Exchange 2007 audit script soon, so stay tuned.


Measure the SMTP roundtrip time to an external email address

Posted by Jean Louw

In an attempt to be more proactive about Internet email delays, whether caused by our systems, or those of our ISP, I have written a script which tests the roundtrip time on SMTP mail.
The basic idea behind the script is to send a message with a GUID, and wait for the return of that specific message. When that message returns, it measures the roundtrip time, and logs the result to disk. If the message is not returned within 30 mins, it will send you a warning message informing you of the problem.

Finally, the script creates a nice JPG with the results up to the last run.

Setting up and using this script is a little more complex than usual as it combines different technologies and resources to achieve its goal, which is to measure the roundtrip time on an actual SMTP message.
To start off, the script sends a message using a standard .NET relay. On Powershell V2 you could use send-mailmessage instead. At this point, the message is time stamped in the subject, with the current date and time. The message is also marked with a distinguishable word “SMTPPing” for the reply rule, and a random GUID, which aids in recognising the message when it returns.

I use Gmail, as my “auto-reply” robot, as I am fairly certain that their infrastructure is robust and pretty stable. If you choose to use Gmail, you will need to setup a filter, which automatically forwards all mail with the word “SMTPPing” back to your email address, and then deletes it from Gmail.

Once you are sure that the auto reply is working, you can configure the script with your SMTP email addresses and relay host.

The return messages are collected from an Outlook mailbox using MAPI. You need to customise the script for the Outlook profile it needs to logon to. More details regarding this can be found as comments inside the script.

Outlook does not like strangers poking around in your stuff, so it will constantly warn you about this. To get around this problem, and also be a little selective about what you allow, you can download an awesome free tool from MapiLab called Advanced Outlook Security.

Lastly, the script needs Excel installed, in order for the chart creation and export to JPG.

I am not sure why, but I am having problems currently closing Excel. Although I issue the command to close the application, it sometimes remains running, so lookout for excel.exe in process monitor.

As usual, your comments and suggestions are always welcome.

If you like this script and use it in production, please help me keep this project free by considering a small donation.

The script can be downloaded from here: