Legacy software blues
Is the legacy software platform holding the projects back? Virtualization can offer a safe and affordable path forward.
When integrators do a really good job, sometimes we give our clients a false sense of permanence. The rock solid system you set them up with performs flawlessly. So well, in fact, that they never have to think about it, much less considered upgrading. Why would they when their current system works, operators are familiar with it and, most importantly, it’s paid for?
But as the years add up, some important dates come and go. First, the software maker’s window of support closes. Support for the OS is the next thing to expire. Before long, your client is counting on obsolete software running on an aging server to keep their plant going. There’s a time-bomb sitting on their server rack and it’s not a matter of if it will go off, it’s when.
This was the scenario we were presented with recently by a long-time customer. Many years ago, we had installed two redundant HMI servers, both running RSView32 on Windows Server 2000 (SP2!), and the cracks were really starting to show. HMI clients were freezing up mysteriously and the customer could see their venerable old system was on its last legs.
Clearly they were due for an upgrade, but they weren’t ready to commit it. That scope of work just wasn’t in their budget and they needed a fix now. The challenge became to craft a solution that would meet their needs in the short run and position them well for future upgrades.
After some careful consideration we decided virtualization was the optimal solution because it provides our client with the most flexibility for future development while allowing virtual machine copies of the existing servers to safely remain on the network. Installing two new host servers would maintain the failover redundancy, give plenty of room to virtualize other machines over time and provide a platform for the seamless transition to a new HMI system in the future.
We planned to deliver freshly installed virtual instances of the Server 2000 machines onthe new host servers, but we wanted to make clones of the originals to have for reference off-site. Ideally these clones would be taken without interrupting production at the plant through a process called hot-cloning, but the OS doesn’t exactly make that process easy.
Server 2000 was the last server OS Microsoft released before adding Volume Shadow Copy Service (VSS), which is what most physical-to-virtual (P2V) conversion software packages use on to make clones. Without VSS, and because it’s so rarely seen in the wild these days, I wasn’t able to find a current P2V software package that will support a Server 2000 conversion.
One of the most popular packages is VMWare vCenter Converter, and its most current version is 6.0. The last version to support Server 2000 was VMWare Converter 3.0.3 Build 89816, and because VMWare no longer supports this version you can’t download it from them directly. Thankfully, a quick Google search led me right to it.
Converter 3.0.3 comes in two flavors. The hot-clone version requires an installation on the machine you want to clone. The cold-clone version is a bootable disc that will allow you to clone without a software footprint, but you have to take the server out of production to make the clone. If you’re looking for that ISO you can find it in at That… Could Be a Problem courtesy of blogger and VMWare expert Kyle Ruddy. The ISO is built on Windows PE and has a healthy set of drivers onboard, but you may have to slipstream some in if the ones you need aren’t included.
With either version, a simple wizard will walk you through the process and gather your relevant parameters like destination and machine name. If you’re thinking of cloning to an external USB drive, remember there is a limit on the size of the discs recognized by Server 2000 that varies depending on your Service Pack level. For this reason, I recommend using the local disc or a network share as the destination.
When the cloning process is done, you’ll have a .VMDK file with a (hopefully) working copy of your cloned machine. At this point you have lots of options. If you plan to use a VMWare product to run your VM, I recommend using VMWare Workstation’s Change Hardware Compatibility tool to upgrade the version of your VM to Workstation 11. The highest level supported by VMWare Converter 3.0.3 is Workstation 6 and I wasn’t able to boot my clone in VMWare until I performed the conversion because of a pesky BIOS error.
You can also take your .VMDK file and convert it to a .VHD format using a nifty freeware tool called Vmdk2Vhd. Once you have it in .VHD format, you can run your VM with Oracle’s Virtual Box or with Microsoft Hyper-V.
Remember, the process I just described is specifically for a Server 2000 machine. If you’re cloning anything with a newer OS, find the most up-to-date conversion tool that will support it. The newer the version, the better chance you’ll have of getting a good result.
Timely upgrades are always best, but virtualization can help you squeeze that last bit of life from your customer’s legacy software while you lay the groundwork for system upgrades. It’s a powerful tool that gives you and your customer lots of valuable options, both now and for the future.
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This post was written by Tim Gentry. Tim is an engineer at Maverick Technologies, a leading automation solutions provider offering industrial automation, strategic manufacturing, and enterprise integration services for the process industries. MAVERICK delivers expertise and consulting in a wide variety of areas including industrial automation controls, distributed control systems, manufacturing execution systems, operational strategy, business process optimization and more.
Maverick Technologies is a CSIA member as of 7/15/2015