How to avoid duplicate computer SIDs when building machines from an image

I’m building a test lab that requires a number of Windows Server 2003 Server Pack 1 virtual machines and hence I’ve built a single image and have replicated it for each instance. To avoid the problem of each machine having the same identity (computer SID) at the O/S level I’m using a cool utility named “NewSID”. John Howard put me onto this utility – it’s cool because it’s so simple and unlike “Sysprep” it doesn’t result in bloated virtual machines and it’s free.

Click here to browse to the “NewSID” section of the excellent SysInternals website to find out more.

Comments (4)

  1. Joe Wannabe says:

    "it doesn’t result in bloated virtual machines…"

    What do you mean by that?

  2. Steve Lamb says:

    Joe> My experience has been that running Sysprep on an image results it’s size growing considerably – I haven’t found that to be the case when using NewSID. Do you have different experience? If so I’d love to hear it.

  3. danielvs says:

    Hi Steve, You really never used NewSID before? Shame on you! 🙂 I never use sysprep for building demo’s and like you and John also prefer NewSID for avoiding duplicate SIDS. Pay attention to the virtual MAC adresses in the VMC files for your lab. I had an unexpected AD problem once because the random created MAC adress existed twice! Cheers, Daniel

  4. Alistair Gillespie says:

    The reason most people are using the MS supplied tools is for supportability : "Microsoft does not provide support for computers that are set up by use of SID-duplicating tools other than the System Preparation tool. If an image was created without the use of sysprep, Microsoft does not support the running of Sysprep after the image is deployed…" Maybe you should have a word with the team about fixing sysprep if you think it causes unnecessary "bloating" – then we can all benefit from using a supported tool.