There are a number of tasks that are easier, safer, and less costly if run in virtual machines (VM) instead of physical computers. One example is testing beta (or alpha) software. By its very nature, beta software can contain bugs—even quite serious and damaging bugs. Run beta software on your main PC, and you run the risk of real problems that could take a long time to recover from. Purchasing or borrowing another PC just to test beta software is expensive and time-consuming. But if you run that same beta software in a VM on your main PC and then throw that VM away—no risk at all.
Another example of a task better done with a VM (and the subject of this blog post) is running two pieces of software that are mutually incompatible. For example, there is no way to run Safari 10 and Safari 11 simultaneously on a Mac. Not only can they not be run simultaneously, they can’t even be installed side by side. This is also true for multiple versions of Internet Explorer.
Purchasing another PC just to run these incompatible applications is also expensive and time-consuming. However, a web developer or web tester needs to test a site with multiple versions of different browsers, since different versions are used by different people who might access the site.
Take a look at Figure 1. You can see that I am simultaneously checking a webpage in five different versions of IE and two versions of Microsoft Edge. I can see issues in any of these, fix them, and see the result in all seven browsers at once—an extremely efficient way to work.
Similarly, Figure 2 shows the same thing being done in four versions of Safari.
Certainly, I could purchase and maintain a whole room of extra computers to run these incompatible applications, but this would be expensive, time-consuming, and inefficient.
Rather, what I have done is run each of these applications in different VMs, all running on my Mac using Parallels Desktop® 13 for Mac. With Parallels Desktop, you can install as many VMs as you have space for on your Mac hard drive, and you can run as many simultaneously as you have RAM for.
Figure 3 shows the complete list of VMs I have installed on my MacBook Pro®. With the 16 GB of RAM on that Mac, I can run about eight VMs simultaneously, if needed. I admit, however, that I don’t run that many VMs simultaneously very often.
Are you interested in setting up this many VMs and running them simultaneously? Stay tuned, since that will be my next blog post.