Most commonly, most users only have one operating system installed. Specifically Windows. This is the system that they start up by default, and they use until they turn off the computer until the next day. However, there is a technique by which it is possible to install two, or more, operating systems on the same computer, being able to choose which of them we want to boot at any time. This is what we know as dual boot, or Dual Boot .
The Dual Boot is a configuration with which we can install two operating systems on a hard drive (different partitions) or on several hard drives so that, using a boot manager, we can choose which system we want to boot every time we turn on the computer.
Main advantages of the Dual-Boot
It is true that dual booting is not for everyone. It is rare to need two or more operating systems at the same time, or to have special needs that we cannot meet by virtualizing a second operating system. But it can happen.
Dual-Boot systems allow us to run two real operating systems on the same computer . But not at the same time. The main advantage of this is that we will be able to have physical access to all the resources of the PC (processor, graphics, etc.) and we will be able to take full advantage of the performance of these components. In this way, for example, we can use Linux to work (since it is more secure and generally consumes fewer resources), but we can load Windows at the end of the day and start playing on the PC.
Real access to hardware is undoubtedly the best advantage of this type of setup. But we can also have other advantages. For example, if one of the systems fails, we can start any of the others and access its partition to be able to repair it, or, at least, recover the data. This is useful if our work depends on the computer, since with a dual boot we can always have an alternative operating system with which to work if the main one fails. And when we finish working, we can try to repair the first one.
Also, if we like to test different operating systems (such as Windows, Linux, and even macOS), the best way to know how they work and enjoy all their features is to do it through a real installation, not in a virtual machine.
Disadvantages of the Dual-Boot
Having two operating systems on the same computer is very useful, yes. But the first thing to keep in mind is that they are not going to run at the same time . Every time we want to change the operating system we will have to save the changes, close the open programs and restart. And be aware of the boot loader to choose the system we want to boot. This can take between 2 and 5 minutes, a time that we can save if we use a single operating system.
In addition, the configuration of the Dual Boot is anything but practical and simple. In normal conditions, what we would have to do is install the operating systems, one after the other, until we have them all. The last system, which should be Linux, will detect all other operating systems, and add their GRUB entry . When we start the PC we will see the GRUB boot loader of this system, and we can choose which one we want to load.
Although the theory is simple, in practice we will run into problems. An update, from either system, is very likely to overwrite the bootloader and load yours . In that case, we will have to reconfigure it. If the boot is damaged, we will lose access to all operating systems, and reconfiguring a boot without installing an OS is not exactly easy.
And if we think about installing a Dual-Boot with macOS (what we can call Hackintosh), things get much more complicated. The Apple operating system requires specific changes in the BIOS / UEFI of our computer, changes that can make the other systems not work, or do not work correctly.
The safety (or rather, lack of it) is another of the disadvantages of such configurations. For example, we can unintentionally download a virus from Windows, and this virus will affect all operating systems. We can even download a virus from Linux, and this, although it does not affect this OS, will be configured to run the next time we start Windows. In addition, unless we use some type of encryption, all operating systems will be able to access the data of the other systems. And that is more dangerous.
Virtual machines: alternative to Dual Boot for everyone
There is an intermediate point with which we can use other operating systems without having to resort to this type of configuration: virtual machines . A virtual machine, for those who do not know it, is a program that is responsible for virtualizing the hardware of a real PC and allows us to install an operating system on it.
These virtual machines generally do not have access to the physical hardware of the PC, which is noticeable in the end in the general performance of the system that we emulate. For example, we can forget about playing state-of-the-art games. And we cannot know for sure whether an operating system works well or not when running on virtual hardware. However, it has many other advantages.
The first of these advantages is that it is much easier to assemble. We do not have to configure anything, since everything is in charge of the corresponding program that we choose (VMware or VirtualBox). The hard disk is a file that is stored on our physical disk, and that we can open it on any PC from the same program. Everything we do inside this machine will remain inside it, and at no time will it endanger our real PC.
Thanks to virtual machines we can run two, or more, operating systems at the same time . It will be enough to be, for example, in Windows, and open the machines that we have configured as another Windows, a Linux and macOS. We can use them all at the same time, and even connect them through a virtual LAN. And we will have control of the machine at all times. To the point that, when we get tired, we can eliminate it in seconds.