Most people I talk to have never heard about our Rapid Cloning Utility for VMware (RCU). This tool however is the magic behind the rather famous youtube videos that show how NetApp can very quickly create and deploy a very large number of VMs while using very little disk space on the array. With VDI being VERY hot right now (I have 5 projects on the go!) this is a great tool to get to know and use. The tool is now available on the NOW tool chest and is free. I had an opportunity to really test this tool out and thought I would share a few things and also look a little beyond the initial deployment to how would you perform routine tasks using this tool.
The RCU set up very fast and was incredibly easy to use. Hats off to the team that built this. There is a little fine print that you need to read and be sure you do before hand prior to using the script. Like most IT guys, I rushed in and then had to start over properly to make sure everything was right. First, in your golden volume, you need a batch of VMDK files in a folder. Essentially build up your master image that you want cloned. If your are like me and using a Windows XP image, be sure to install the LSI SCSI drivers in the VM BEFORE cloning it. You need those drivers after the mass deployment. Once you have the image just as you want it, clone the VMDK as many times as you want VMs in a volume. For me, I was testing a block level install so I did 25 VMDKs in the volume. I used another tool for that which was the rfwm tool which also worked like a charm. Another tip here though, you want ONLY VMDKs in that folder. I deployed a VM to the folder and then cloned the VMDK files giving me 25 VMDKs and the other files associated with the original VM. This gives you some phantom VMs when you use the RCU (I think it tries to build VMs and attach them to vmx files instead of VMDK files. Easily corrected tough. Once this was done, I deduplicated the volume, took a snapshot of it and started cloning.
I had many, many VMs within minutes and was very impressed how the VMs were properly named, organized and customized. Awesome! So what now? How would you use this tool going forward?
More VM’s Please
Dropped my command line into a simple .bat script sitting on my desktop. This way everything I needed another 25 VMs I could just double click the icon and poof, there is another 25 VMs. Very easy.
New Folder
I have to ask the developer but I learned that the VMs are created in whatever folder the VM Template lives in. Good to know. Since the VM templates have no disk file they are very small so it would not hurt to create multiples of them. Perhaps you have VMs that share that same disk image but you need some VMs with more memory than others Very easy to create multiple templates and then just choose which template to use for the cloning. All the clones will share the templates memory, cpu and resource settings.
Patching
Here is one I get questions about all the time. How do I patch? Well you have 3 options here.
1. You can simply patch all the existing VMs as you would physical desktops. You need enough space to hold all the patches but you would then run dedupe against each volume and reclaim that space back. For your base image you will either have to patch all the cloned VMDK files or destroy them, patch the original and reclone, the second option being the easiest. This is the preferred method for customers having persistent desktops.
2. If you have non persistent desktops, that is, users are not assigned one particular desktop, you can patch the original VM, create more clones from the patched image and then start to migrate users from the old image to the new. Most connection brokers will allow you to stop connecting users to one folder and start connecting them to another. By doing this users will simply get a newly patched VM the next time they log in. Once everyone has disconnected off a folder of the old VMs. You can unregister the VMs and delete the volume off the NetApp controller.
3. The 3rd option is to simply destroy all the clones during an outage and reclone them back out. The tool runs so fast that is a very viable option if your VDI farm isn’t used 24X7
I know the team is hard at work on version 2 of the tool so I can’t wait to see that! Let me know if you have questions or want to know how you would perform a particular task using the RCU.
Keith
