Installing Operating Systems – CompTIA A+ 220-1102 – 1.9

There are many different methods and techniques for installing an operating system. In this video, you’ll learn about boot methods, types of installations, disk partitions, and formatting options.

If you’re installing an operating system, you need some type of media that will hold the operating system software and allow you to start the installation process. One very common way to do that these days is with a USB drive. You would first create a bootable USB drive. There are a number of different utilities available across different operating systems that can do this. And then you would install all of the operating system installation files to this USB drive.

You would then configure the BIOS of your computer to be able to boot from this USB drive. On an older system, you might have an optical drive, and all of your operating system files would be contained on a CD-ROM or DVD-ROM. Of course, in an enterprise where you have hundreds or thousands of computers that need to have operating systems installed, you would probably have a remote method of performing this installation. One common way to do this is through PXE.

This PXE stands for pre-boot execution environment, where you can install this operating system across the network. With PXE, you would configure a centralized server on your network that has all of the operating system installation files. You would then boot your computer into this PXE, or PXE, mode, and it would search across the network to find that server and begin the installation process. And of course, you could install all of these operating system files onto a hard drive or SSD and use those drives to boot your system.

It’s not uncommon for the installation process of these operating systems to use an updated set of files that it can download directly from the internet. This is very common when you perform Linux distributions, where all of the files are downloaded directly from servers on the internet. macOS has a similar functionality when you use the recovery installation and it downloads the files directly from Apple. And if you’re installing Windows, there are Windows updates that can be retrieved directly from an update server.

You can also have all of this information stored on a separate external, or hot swappable, drive that you can plug into any available USB connection. Some of these external drives support an ISO mode, where you can install the ISO file onto the device and then have this system boot up and have it appear as if it is a single optical drive. Or of course, you could copy all of the operating system files onto the drive that’s inside of this USB enclosure and simply connect and use that as an external drive.

If you don’t have a way to install the operating system using these external sources, you could try installing a new hard drive or SSD and run the installation process from that drive internally on your system. This is obviously a bit more complex than simply plugging in an external USB drive, but it does give you access to all of the necessary installation files. If you’re moving from one operating system version to an updated version of that OS, you can commonly perform an in-place upgrade.

This leaves all of your applications in place. It leaves all of your data files installed on that operating system and simply upgrades the underlying operating system on that computer. Many computers will come installed with a separate recovery partition on the storage drive itself. So instead of trying to find the correct installation media that may or may not have been shipped with that computer, you can simply start the installation process from that recovery partition.

If you don’t want to keep any of the applications or any of the data on that system and you would like to install a fresh version of the operating system, you can perform a clean install. This will effectively delete everything that’s on this partition. So you want to be sure to have a backup of all of your personal files. Some operating systems will include a migration tool that will perform a backup, allow you to perform the clean install, and then restore your files back to that system once the upgrade is complete.

And if you’re working in a corporate environment, or a large installation with tens or hundreds of computers that need upgrades, you might want to perform an image deployment. You would create a version of the operating system that could be used by anybody in the organization, and then you would use that as a version to copy to everyone’s upgraded system. This means that everybody gets exactly the same configuration. And if you ever need to replace the system, you simply override it with that image.

If you’re running into problems with an operating system and you’d like to install the same operating system on top of it as a way to troubleshoot, you’d be performing a repair installation. This doesn’t modify any of the user files or applications. It simply updates, or refreshes, all of the operating system files for that version. At home, we might have installation media that we would plug into our computer, but in a corporate environment, where all of your systems are networked, you don’t need to carry around separate installation media.

You simply start the system and point it to a server that’s central on the network. This is a remote network installation, and it can be to a local server, or a shared drive on your system, or you could install the entire operating system across the internet. Although most operating system installations include all of the drivers you would need to get running, you may run into situations where certain hard drive controllers or other pieces of hardware won’t work properly during the install.

In those cases, your operating system may have a way to install drivers during the installation process so that you would then have access to the hard drives and other critical hardware components. If you’re starting this operating installation on a brand new, fresh hard drive, you’ll first need to create an area where you need to store the operating system. We refer to this large area as a partition. It’s a way to logically separate different areas of the drive.

You could store different operating systems in different partitions or simply use it as a way to organize your data files. So you might have a computer where you’ve installed Windows into one partition, and then you’ve created a separate partition just for Linux. This might allow you to reboot the system and choose what operating system you’d like to use during the startup process. If you’re using a Microsoft operating system, you’ll commonly see these partitions referred to as volumes.

There are minor differences between what Microsoft calls a volume and what the rest of us call a partition, but for the purposes of what you’ll be doing in the operating system, you can consider them to be the same thing. If you’re installing an operating system these days, you’re installing a partition called a GPT partition style. GPT is short for GUID partition table. That GUID is also an abbreviation that stands for globally unique identifier.

When you create this partition, it assigns it with a unique identifier that no other partition has in the world, which is why we call it a globally unique identifier. If you have a UEFI BIOS, then you can install this GPT partition style. On a single physical drive, you can have up to 128 GPT partitions. The maximum size is over 9 billion terabytes, and in Windows, the maximum partition size is currently set to 256 terabytes. If you’ve worked with some of the older MBR type partitions, then you know there’s a difference between having extended partitions and logical partitions.

But with the GPT partition style, all partitions are equal, and you can have up to 128 of those GPT partitions. That older style of an MBR partition stands for master boot record. This is a partition style that you’ll find a much older operating systems. For example, an MBR partition has a limitation of only two terabytes as a maximum partition size. And given the large size of drives that we have today, a two-terabyte partition is very limiting.

MBR partition drives have two different kinds of partitions that you might configure. One is a primary partition. Only primary partitions on an MBR drive are bootable. So if you’re installing an operating system that you need to boot from, it needs to be located in a primary partition. You can only have a maximum of four primary partitions on an MBR partition style drive. This is obviously very different than the 128 partitions you can have on a GPT partition style.

When you create a primary partition on an MBR drive, you mark one of those as an active partition. This way your system knows what operating system should start automatically during startup. If you need more than four separate partitions on an MBR partition style, you would then use an extended partition. This allows you to create many more partitions on the MBR partition style, but none of these partitions are bootable. So you can’t install an operating system into an extended partition and then try to boot from that operating system.

You can see why having a GPT partition style gives you so much more flexibility because with GPT, you can create 128 partitions and then boot from any of those GPT partitions. Once you decide whether you’d like to use GPT or MBR, you can then create that logical partition. If you’re installing a new drive, you may find that drive has already been partitioned. You may choose to use this existing partition or to delete the partitions on the drive and create the partitions yourself.

Remember that an MBR drive can only support four partitions, but if you’re using a GPT-formatted drive, you can have up to 128 partitions. The process of creating or removing a partition will delete data from your system. So if there’s any data on this computer now, make sure you have a backup before making any changes to the partitions. The partition process occurs during the Window set up during this dialog box that asks where do you want to install Windows.

And it will list any partitions that are currently configured on this drive. You can choose to add more partitions to this drive, you can extend the size of existing partitions, or you can delete what’s here and create new partitions. Once you create the partition, you’ll then need to create the file system that will be stored on that partition. And the way that you create a file system is with the format command. In Windows, there are different ways to format the drive.

One is through the use of a quick format. This creates the file table on the drive, but it doesn’t delete or overwrite any of the existing data that may already be on that storage device. This means if somebody accidentally performs a quick format, there’s still a possibility of recovering the data that’s on that drive. If you’re installing Windows 10 or Windows 11, the quick format process is the default format that will occur during the installation. If you want to perform a full format, then you’ll want to use the diskpart utility.

A full format overrides all of the data on the drive because it’s writing zeros to every sector of that storage device. If you have any data that’s stored on that drive, it will be overwritten, and everything that was previously there is unrecoverable. This is why we often say that if you’re going to make changes to a partition or run any type of format that you make sure that you have a backup of all of your data.