Archive for November, 2009

The other day I applied Update Rollup 1 for Exchange Server 2007 Service Pack 2 in my test lab and wanted to check that the update was successfully applied.  Being something of a Powershell fan I first tried the command shown below:

(get-exchangeserver MyE2K7Server).admindisplayversion

The output showed Version 8.2 (Build 176.2), which is the same as Exchange Server 2007 SP2 without the Update Rollup.  Next I look at the value using the Exchange Management Console (EMC), which showed me the same information. 

I even checked the registry under HKLM\SOFTWARE\Microsoft\Exchange\v8.0\<role> and the ConfiguredVersion value shows the same (8.2.176.2). 

The only place I noticed the build number had been incremented was in the EMC under Help->About. 

Successful installation of an update rollup should not be ascertained by the version number shown in the admin tools.  The version number displayed by Exchange Management Console or other administrative mechanisms is obtained from the Exchange Server Object in Active Directory.  If we update the Exchange Server Object in Active Directory to show a new version number for every rollup, it would require additional privileges for the account being used to install the rollup.  Since many large customers have split level administrative model where the Exchange administrators do not have permissions to the Active Directory we do not update the Active Directory with an updated version number when the rollup is installed. 

Another factor is that the rollup is no different than a Hotfix/Update for other products from Microsoft.  So as an administrator you should do what you usually do for validating that the Hotfix is correctly installed/ In Windows Server 2003, you will need to go to Add//Remove programs in control panel and make sure the “Show Updates” checkbox is selected at the top.  In Windows Server 2008, you will need to go to “View Installed Updates” in the Control Panel. 

Ananth’s method is fine you want to look at one Exchange Server, but what if you want to list the build levels for all Exchange servers in your organisation?  Powershell to the rescue!  Here’s a script I put together to show the names, editions and build numbers for each Exchange server in the organisation. 

Windows Server 2008 R2 introduces the ability to revert to an earlier forest or domain functional level.  Previous versions of Active Directory did not have this ability and raising the forest or domain function level was, effectively, a one-way operation.  I say “effectively” because it is possible to revert, but only through highly disruptive recovery operations (full forest recovery in the case of a forest functional level upgrade). 

I’ve actually not experienced or even heard of anyone having serious problems following a functional level upgrade, but that’s not really the point.  Have you ever tried to get approval from a Change Manager when your proposed backout plan involves a full forest outage of 12 hours or more?  In providing a mechanism for reversing a functional level upgrade, Microsoft has responded to customer demand for peace of mind, rather than a fix for a known problem. 

This article shows how to raise the forest functional level and then revert it using Powershell commands.  The screenshots shown below are from running the commands in Powershell ISE. 

On a Domain Controller, open a Powershell prompt and (assuming you don’t already have it) import the Active Directory Powershell module. 

After enabling the AD Recycle Bin you will receive the error below if you try to revert the functional level. 

Another limitation is that you can currently only revert from Windows Server 2008 R2 functional level to Windows Server 2008 functional level.  In other words, the feature has not be retro-fitted to support earlier functional levels. 

As you can see, raising and reverting the functional level is fairly straightforward operation once you have the appropriate Powershell commands.  It should give you (and your Change Manager) a degree of comfort when planning your upgrade.