Duplicating a virtual machine for testing/development purposes

I have a fairly big project coming up in which I need to upgrade a third party application currently running on a hyperv 2008 R2 host. The application and its backend database reside on the same VM. The client portion of this application resides on a separate VM also running on a hyperv 2008 R2 host.

Instead of performing the upgrades on the production systems I want to create duplicate/mirror copies of these two systems. Unfortunately, I do not have a test/development network segment to put these system in and I believe they will require access to resources in order to function properly. Resources such as Active Directory.

My plan is to simply take a copy of the .vhd files, attach them to newly created VMs. Bring the VMs up with no network connection:
- change the name
- change the IP address
- join them back to the domain after renaming & readdressing them and turning network connections back on.

Am I missing a step? Should I sys prep these systems in order to remove the SIDs, etc?
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Jayaraja JayaramanSharepoint Architect ConsultantCommented:
also if there any custom developments or anywhere the urls are hardcoded then you will be in trouble...
Sir LearnalotCommented:
Yes, sys prep the machines otherwise you may have a conflict with the existing machines
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
You only need to Sysprep the machines if using in Production and for various management, e.g. System Center and WSUS.

When you change the name, IP Address, and add back to the domain, the machine will be fine, and will not "conflict" with an existing machine! The re-joining of the domain, will give you Domain SID.

It's the Machine SID, which Sysprep can change, and other machine-specific info used by WSUS and System Center.

you can have a read of the following:-

from the article

The final case where SID duplication would be an issue is if a distributed application used machine SIDs to uniquely identify computers. No Microsoft software does so and using the machine SID in that way doesn’t work just for the fact that all DC’s have the same machine SID. Software that relies on unique computer identities either uses computer names or computer Domain SIDs (the SID of the computer accounts in the Domain).

The Machine SID Duplication Myth (and Why Sysprep Matters)

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Liam SomervilleSenior Security ConsultantCommented:
If there is any way you can migrate your VMs to an isolated test server, that would be best. All you'd need is a license for 2008 R2 since Hyper-V is free. That way you avoid the headaches re-integrating your machines to a production network and give yourself a safe place to do this kind of testing in the future.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Windows Server 2008

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.