Linux is often best installed in a dual-boot system. This allows you to run Linux on your actual hardware, but you can always reboot into Windows if you need to run Windows software or play PC games.
Here’s the basic process you’ll need to follow:
- Install Windows First: If you already have Windows installed, that’s fine. If not, be sure to install Windows first, before you install the Linux system. If you install Linux second, it can set up its boot loader properly to happily co-exist with Windows. if you install Windows second, it will ignore Linux, and you’ll have to go through some trouble to get your Linux boot loader working again.
- Make Room for Linux: You’ll need free space on your Windows system drive to install Linux, or possibly a second entirely different hard drive if you have a desktop PC. You’ll usually need to resize your Windows partition to make room for Linux. If you’re installing Windows from scratch, be sure to leave some free space on the drive for Linux. This will save you some time later.
- Install Linux Second: Choose your Linux distribution and put its installer on a USB drive or DVD. Boot from that drive and install it on your system, making sure you select the option that installs it alongside Windows — don’t tell it to wipe your hard drive. It’ll automatically set up a Grub2 boot loader menu that lets you choose your preferred operating system each time you boot your computer.
Although the broad outlines are simple, this can be complicated by a number of issues including UEFI Secure Boot requirements on Windows 8 PCs and disk encryption.
Install Windows First
Your PC probably already has Windows installed on it, and that’s fine. If you’re setting up a PC from scratch, be sure to select the “Custom install” option and tell Windows to use only part of the hard drive, leaving some unallocated space left over for Linux. This will save you the trouble of resizing the partition later.
Make Room For Linux
You’ll probably want to resize your Windows system partition to make room for Linux. If you already have some unallocated space or a separate hard drive for Linux, that’s perfect. Otherwise, it’s time to resize that existing Windows partition so you can make space for a new Linux partition.
You can do this in several ways. Most Linux installers allow you to resize Windows NTFS partitions, so you can do this during the installation process. However, you may just want to shrink your Windows system partition from within Windows itself to avoid any potential problems.
To do so, open the Disk Management utility — press Windows Key + R, type diskmgmt.msc into the Run dialog, and press Enter. Right-click the Windows system partition — that’s likely your C:\ drive — and select “Shrink Volume.” Shrink it to free up space for your new Linux system.
If you’re using BitLocker encryption on Windows, you won’t be abne to resize the partition. Instead, you’ll need to open the Control Panel, access the BitLOcker settings page, and click the “Suspend protection” link to the right of the encrypted partition you want to resize. You can then resize it normally, and BitLocker will be re-enabled on the partition after you reboot your computer.
Install Linux Second
Next, make installation media for your Linux system. You can download an ISO file and burn it to a disk or create a bootable USB drive. Reboot your computer and it should automatically boot from the Linux installation media you’ve inserted. If not, you’ll need to change its boot order or use the UEFI boot menu to boot from a device.
On some newer PCs, your PC may refuse to boot from the Linux installation media because Secure Boot is enabled. Many Linux distributions will now boot normally on Secure Boot systems, but not all of them. You may need to disable Secure Boot before installing Linux.
Go through the installer until you reach an option that asks where (or how) you want to install the Linux distribution. This will look different depending on your Linux distribution, but you want to choose the option that lets you install Linux alongside Windows, or choose a manual partitioning option and create your own partitions. Don’t tell the installer to take over an entire hard drive or replace Windows, as that’ll wipe away your existing Windows system.
Choosing an Operating System and Customize Grub2
Once you’ve installed Linux, it will install the Grub2 boot loader to your system. Whenever you boot your computer, Grub2 will load first, allowing you to choose which operating system you want to boot — Windows or Linux.
You can customize Grub’s options, including which operating system is the default and how long Grub2 waits until it automatically boots that default operating system. Most Linux distributions don’t offer easy Grub2 configuration applications, so you may need to configure the Grub2 boot loader by editing its configuration files.
You can use this process to triple or quadruple-boot multiple versions of Linux along with Windows, multiple versions of Windows along with Linux, or multiple versions of each. Just install one after the other, ensuring there’s enough room for a separate partition for each operating system. Be sure to install Windows before you install Linux, too.
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