Troubleshooting poor performances of virtual machines in an Oracle VirtualBox

Sometimes I have to give a presentation on IT. I like to make a such presentation to be dynamic, combining together slides and a live demonstration. I often use several VMs in the same time to simulate scenario.

Preparing one such presentation, I made a few mistakes in the configuration of the VMs. Eventually, one VM was too slow during startup. An audience on the presentation didn’t noticed the problem, as I covered it up with an another part of the demonstration.

After the presentation, I analyzed the whole situation and found the weak point – the wrong choice between VM’s parameters.

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Optimizing performance of the virtual machines in an Oracle VirtualBox

The Mikrotik User Meeting or MUM Serbia 2016 was only a few days ago, during which I delivered a presentation related to the Mikrotik IPSec services. Rather than repeat the presentation, I decided to combine the slides and live demonstration.

I will write about Mikrotik IPSec services in some another post. I mention this presentation because the demo part is important for today’s though. One of the virtual machines booted very slowly and this had some impact on the presentation.

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Exporting virtual machine as an appliance in the Oracle VirtualBox

In previous post we saw how to duplicate a virtual machine as a linked clone of existing virtual machine. As result, we have a new virtual machine identical to original. New virtual machine is on the same host as an original virtual machine. We also have a benefit of smaller occupied space on the hard disk of the host machine.

However, if we need to transfer some virtual machine on the other virtual host or to import it a few times, we’ll need different approach. We can make a template and then we can reuse it multiple times.

This template is one single file, containing all necessary files and information to successfully generate new virtual machine on the same or other virtual host. During deployment process we can change some parameters and then adapt new virtual machine to our environment.

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Using linked clone of virtual machines

Virtual machines are so common today. We can use them for different purposes, from a test facilities to the production environment. Main advantages are faster deployment, resistance to hardware failures and easier reverting to previous known good state.

Today we have wide choice of virtualization systems. We can choose virtualization software that needs regular operating system, like Windows or Linux, or a stand-alone virtualization solutions, that we can install on the bare metal chassis.

I will show you how to use Oracle Virtual Box version 5.x to build your own virtual lab. You can perform all those tasks on similar way in many other solutions. However, not all solutions can offer all options mentioned in this article.

We can speed up deployment and save precious resources in same time, if we’re using a virtual machine clones. Process is very easy. We should install bare operating system and all necessary drivers on machine with minimal requirements for a normal work. That’s all in first step.

Then we will use that virtual machine (VM) as a foundation for all other VMs. We’re saving time on new installation and basic configuration for every new machine. Therefore, this machine will be considered as template for all new similar VMs.

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