Remko Weijnen's Blog (Remko's Blog)

About Virtualization, VDI, SBC, Application Compatibility and anything else I feel like

Archive for June, 2011

I have used the WP-Postviews WordPress plugin for a while to keep track of the number of times my blog posts are being read.

But after installing the W3 Total Cache plugin I noticed that the read counters weren’t properly updated anymore. I figured this was a consequence of using a cache.


  • Filed under: General
  • AD Internals: Display RID Allocation Pools

    In my previous post I wrote about a problem I had with duplicate RID Allocation pools.

    But how do we get more insight into these RID Allocation pools?

    The DCDIAG tool can display this information per domain controleler using the following syntax

    Example output:

    DCDiag Ridmanager Test

    But where in Active Directory is this information stored and can we display it for all Domain Controllers at once for larger environments?


    The case of the duplicate SID’s


    I encountered another interesting error during Exchange 2010 installation today. During the Organization Preparation I got the following error:

    The requested object has a non-unique identifier and cannot be retrieved.Active directory response: 0000219D: SvcErr: DSID-031A0FC0, problem 5003 (WILL_NOT_PERFORM), data 0

    The setup.log doesn’t give us much more detailed info:

    I remembered from a Tweet by Helge Klein recently that the Active Directory schema has no mechanism for enforcing uniqueness of an attribute.


    SNAGHTML1ca684cToday I was testing the installation of Exchange 2010 in a VMWare sandbox environment. We created the sandbox to test migration from a 2003 AD and Exchange environment to 2008 R2 with Exchange 2010.

    We used a P2V to get real copies of the Active Directory and the AD upgrade to 2008 R2 was already tested.

    But during the Exchange installation in the sandbox I got the following error:

    The well-known object entry on the otherWellKnownObjects attribute in the container object CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=zorg,DC=local points to an invalid DN or a deleted object.  Remove the entry, and then rerun the task.


    I wanted to read the otherWellKnownObjects attribute from an Active Directory object.

    In my case this was the Microsoft Exchange container in the Configuration partition:


    The otherWellKnownObjects attribute is of type ADSTYPE_DN_WITH_BINARY which unfortunately cannot be viewed or edited with ADSI Edit:

    There is no editor registered to handle this attribute type 



    In my SATA Controller Identification tool I was using the TSaveDialog (Delphi 2010) but I got a report that under Windows PE the dialog is never shown.

    There’s no exception and I didn’t really bother to check why it fails. Instead I decided to replace it with the GetSaveFileName API which does work under Windows PE.


  • Filed under: Delphi
  • Switch SATA Operation Mode

    Modern systems usually offer different SATA Operation Modes such as ATA, AHCI or IRRT.

    The AHCI mode offers extra features such as hot swapping and native command queuing.

    Many vendors set the SATA Operation Mode to ATA by default because it’s the most compatible mode but there are a few reasons why you might want to change it:

    • AHCI has a higher performance than ATA.
    • AHCI is a requirement for the TRIM command.
    • AHCI is required for self encrypting hard drives

    Please note that the IRRT (integrated raid) mode is supposed to support all functionality of AHCI but in my experience it doesn’t.

    So the question is: how do we switch the SATA Operation Mode from ATA or IRRT to AHCI?


  • Filed under: Windows 7
  • Crack WEP Encryption

    I think everybody knows that using WEP to encrypt your WiFi network is not very safe. To demonstrate this I will show you how easy it is to crack the WEP encryption in this post.

    Note that I am using my own Access Point here so I am not actually cracking someone else’s WEP Key.


  • In this post I am using the 32 bit back|track 5 VMWare image which you can use with VMWare Workstation or VMWare player.back|track downloads

    After starting the back track Virtual Machine you can login with username root and password toor

    back track 5 logon screen


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