220-1102 Operating Systems Study Guide for the CompTIA A+ Core Series Exam

Common OS Types

You must be able to identify common OS types and their primary purposes.

Workstation OSs

Workstation operating systems are designed to be used on a desktop or a laptop computer by one person at a time. These operating systems provide a convenient graphical user interface (GUI) and access to files and applications on the computer.

Windows

Microsoft Windows is the most widely used workstation operating system. It can be installed on a wide variety of compatible hardware from many manufacturers, and it is commonly used in homes, schools, and offices.

Linux

Linux is a kernel, the core of the operating system. Interfaces and applications can be added to the kernel. These pre-configured combinations are known as distributions. This flexibility allows users to create various versions of systems for different cases. A distribution can have an extensive graphical user interface (GUI), like Ubuntu, or be better adapted to high performance server tasks, like Red Hat.

macOS

Apple’s MacOS is the operating system designed to run on Apple workstations. It is included with every Macintosh computer and is the second most widely used workstation OS.

Chrome OS

Chrome OS is an operating system designed on the Chrome web browser and released by Google. The Chrome OS is a cloud-based OS with all of its data stored in Google Drive.

Cell Phone/Tablet OSs

Phones and tablets are widely used, growing in hardware and performance, and raising the need for complex, powerful, yet convenient operating systems.

iPadOS

iPadOS is an iPad-specific OS released by Apple that provides better multitasking functionality to the iPad, making it more of a small laptop than a tablet.

iOS

iOS is the operating system on Apple’s iPhones and older iPads. It cannot be installed on devices not manufactured by Apple.

Android

Android is an operating system developed by Google specifically for mobile devices. It is based on the Linux kernel and is free and open source. Many devices from different manufacturers around the world make phones and tablets that run the Android operating system. It is the most used mobile OS.

Various Filesystem Types

The file system allows storing, managing, and accessing files on a partition. A partition is a segment of a hard disk that functions as a separate entity. An operating system usually supports different file systems, and a partition needs to be formatted with a specific file system before usage.

New Technology File System (NTFS)

NTFS is a file system that allows users to set and manage permissions for files and folders for specific users and groups, making it very useful for secure network file sharing. Additionally, it provides indexing (for faster file search), compression, and encryption on the file system level. NTFTS is much more advanced than FAT32 and is supported by all modern Windows versions.

File Allocation Table 32 (FAT32)

Providing very basic features, FAT32 is supported by many operating systems and supports partitions up to 2 TB in size.

Third Extended Filesystem (ext3)

ext3 is a default filesystem for Linux OSs.

Fourth Extended Filesystem (ext4)

ext4 is an updated version of ext3 that supports larger partitions and a larger number of files and improves performance.

Apple File System (APFS)

APFS is proprietary to Apple and replaces the HFS and HFS+ filesystem on Apple OSs. It is the default filesystem on macOS Sierra 10.12.4 and iOS 10.3 and later.

Extensible File Allocation Table (exFAT)

exFAT is designed for small flash and SSD drives and is optimized for performance and media file storage.

Vendor Life-Cycle Limitations

Once an operating system is installed, it can continue running. But there are some limitations that you need to keep in mind and consider updating.

End-of-Life (EOL)

When an operating system reaches the end-of-life phase of its developer, there will be no more updates, patches, or technical support. There will probably be no more applications developed or supported for this OS version.

Update Limitations

When the OS developer stops supporting a specific version, there will be no more security patches released for that OS version. As new vulnerabilities get discovered, this may leave the computer with an outdated operating system exposed to security risks.

Compatibility Concerns Between OSs

Applications that are available for one operating system may not be available for others. The developer of the application may limit its efforts to only one operating system. Some applications may be available for macOS and Windows (for example, Microsoft Office). Some applications may be available for macOS, Windows, and Linux (for example, Google Chrome). In any case, these are different installation files of similar software.

Another compatibility concern may be caused when updating an operating system to a newer version. New versions of operating systems can cause issues with previously installed hardware and applications. Many large organizations choose to not update their operating systems without thorough testing of the new version with the existing hardware and business-critical software.

OS Installations and Upgrades

To start using an operating system, it needs to be installed on the computer. To start the installation process, the computer needs to be booted with the installation media. You must be able to install and perform upgrades in various OS environments. Questions about these concepts will be scenario based.

Boot Methods

A boot method allows the user to select how to boot a computer and what media to use. There are multiple ways to boot a computer.

USB

An external device may be connected to a computer from which to boot. There are many types of external devices, for example: external optical drive, external hard disk, and external flash drive. Common interfaces used to connect the external drives are Universal Serial Bus (USB) and eSATA. A USB flash drive is a very common way to install an operating system.

Optical Media

A computer may have a built-in drive to read optical discs. A computer can be booted from this device with an installation disc. This is another common way to install an operating system on a computer.

Network

A network-based installation is the most effective way to install and upgrade when dealing with a large network. The installation media is uploaded onto a file share with read-only access for the installer.

Solid-State/Flash Drives

An internally connected hard disk may be used to boot. The disk can include the operating system installation image or have the operating system installed. This is the most common way to boot a computer after the operating system installation was completed.

Internet-Based

With an internet-based boot, the information needed to boot is stored and retrieved from the internet via an internet connection.

External/Hot-Swappable Drive

An external or hot-swappable drive can be connected to a device for boot functions. The boot information is stored on the external drive and not locally stored.

Internal Hard Drive (Partition)

It’s important to distinguish between a hard disk and a partition. In many simple configurations, there is one bootable partition on a disk. But one disk can have more than one partition, as it may be useful to have different operating systems on the same computer (multi-boot). Also, one logical partition can span multiple physical hard disks.

Types of Installations

Depending on the current state of the computer, available hardware and environment, and desired setup, there are multiple ways to install an operating system.

Upgrade

This is an installation method that installs a newer operating system over an older one. Depending on the OS and versions, it may preserve the settings, files, and applications.

Recovery Partition

Some operating systems provide an option to create a recovery partition during the installation. It will be a bootable partition that can be used later and contains diagnostic and repair tools, or it may be used for a repair installation.

Clean Install

This installation disregards previous data in the destination. It can be used if the computer doesn’t have any operating system installed or if the intent is to completely delete the previous operating system, files, applications, and settings.

Image Deployment

If many computers have identical hardware and need identical operating systems, settings, and applications, it can be accomplished with image deployment. There are different software tools for this task, but usually the process involves the following steps:

Select one computer.
Perform a clean installation of the desired operating system, configure, and install applications.
Create the image from this computer.
Make this image available on the network or portable media.
Copy the image to other computers.

Repair Installation

Some operating systems provide this option. It is usually initiated by booting with the installation media of the same version of operating system that was previously installed, then selecting the repair option from the menu. It rewrites system files and settings while keeping the user files. This mode may be useful for repair purposes if the installed operating system is not bootable or shows serious issues that can’t be fixed otherwise.

Remote Network Installation

The Preboot eXecution Environment (PXE) network boot can use a remote server with the operating system’s installation files to install the OS on the computer. Depending on the configuration of the server, the installation process may require selecting installation options, just like booting from a CD, or it can be an unattended installation.

Other Considerations

It’s important to consider unplanned consequences of an installation. These potential consequences include data loss, application support, and hardware compatibility.

Third-Party Drivers

Third-party drivers must be compatible with the installed OS.

Partitioning

Partitioning creates one or more logical drives on a physical disk. Each partition can be separately formatted and have a separate file system. In Windows, each partition can have a separate drive letter.

Master Boot Record (MBR)

The Master Boot Record (MBR) is used with traditional BIOS and is the standard partition table. MB can have a maximum of four primary partitions or three primary partitions and one extended partition.

Globally Unique Identifier (GUID) Partition Table

A GUID Partition Table (GPT) contains information on how the disk is partitioned and is used with UEFI BIOS. Compared to the MBR, it supports larger drives and more partitions per drive with up to 128 primary partitions.

Drive Format

Formatting drives when partitioning is included in the Windows installation. Drives can be formatted with a quick format or a full format.

Upgrade Considerations

Here are some other considerations to keep in mind when upgrading and configuring the operating system.

Backup Files and User Preferences

When upgrading to a newer version of the Windows OS, a backup of all files should be made to ensure recoverability if the installation goes wrong. The Windows upgrade process is designed, however, to retain files and most user preferences.

Application and Driver Support/Backward Compatibility

Windows upgrades are typically designed to be backward compatible with older versions. How far back the compatibility reaches depends on the upgrade version. This applies to applications and driver support as well.

Hardware Compatibility

Ensure that the system’s hardware is supported to install and configure the desired operating system. The essential BIOS, CPU, and RAM need to support the installation. The hardware should have supported drivers to be used optimally by the OS.

Feature Updates

Feature updates are available for older OS versions and will continue to be available until the end-of-life (EOL) date for the version. Technicians must be aware of EOL as it relates to feature updates for their OS version(s).

Product Life Cycle

The product life cycle begins when a product is released and ends when the product is no longer supported, its EOL.