Customers that attempted to install the Metrex Cisco Management Pack or the Metrex APC Management Pack under Windows 2003 x64 faced a an unexpected requirement from the installer:

hotfix-req

In addition to the standard requirements for “SNMP Service”, “SNMP WMI provider” and  Powershell v1.0 the installer requires the hotfix 942589. This patch is responsible for fixing the issues with the File System Redirector in Windows x64

Let’s start with the description of what the File System Redirector is in the first place. This service is required for any 32-bit applications to operate normally in a 64-bin environment.

The reason for the redirector is interoperability. Most of the applications are using the Windows’s system components and libraries but in reality most of the 32 bit applications can intercommunicate correctly only with other 32 bit application. This is one of the reasons why Microsoft does include 32-bit version of the most important system components (IIS, Powershell, SNMP, etc…) into Windows x64

The redirector operates very straightforwardly. When a 32-bit application attempts to access a file in C:\Windows\System32, the OS routes the request to a sandbox witch lives at c:\windows\SysWOW64

This folder contains the 32-bit version of the system components that we’ve mentioned before. And the set of the components is amazing – IIS, Powershell and SNMP were mentioned before, msixec, mmc.exe, net.exe, cmd.exe… Even mspaint!

But what happens when a 32 bit application needs to interact with a 64bit application? While the list of the 32 bit components available is impressing, some components do exist only in 64-bit versions. Examples could be powershell comandlets, required to interact with SCOM 2007. For those cases there’s a special path c:\Windows\Sysnative. This allows to bypass the redirector and access files, located in System32 instead of SysWOW64.

Unfortunately this mechanism doesn’t work in Windows 2003 x64 unless you apply the hotfix 942589.

Why is it so important? Our licensing mechanisms were originaly designed for the x86 architecture. While they operate normally under x64, they extensively use the sysnative path to run the 64 bit powershell. So for those who did not upgrade to Windows 2008 but does prefer 64bit system we have bad news and good news:

The bad news is : you will have to install the hotfix and reboot the server after the installation.

The good news is : Our licensing module runs only on the SCOM serveк with the RMS role. You will have to apply the hotfix only to this particular server. SCOM servers with roles of MS, Gateway, Agent are used as SNMP proxies and do not require this hotfix.