A live CD (or “live disc”) is a CD, DVD, or USB drive with an operating system you can boot from instead of the one installed on your computer’s hard drive.
Whether for system recovery or merely a portable disk for guest devices, a live CD offers varied functionality. You can use one to address problems with boot records, lost passwords, and infections.
With Linux, it’s pretty easy to create a DIY bootable live CD. Check out how to build your own bootable Linux live CD, from software to creating a disc and finding an ISO.
Linux Live CD Requirements
Let’s start with the prerequisites. While creating a Linux live CD isn’t terribly difficult, you will need a few items first. Namely, an ISO file, burnable media, and software for writing the ISO.
If you have a spindle of blank DVDs and CDs, this is one way to put them to use. But you may opt to use a flash drive instead. You may well have plenty of USB drives lying around, and a major advantage is that you can reuse these over and over. Plus, this is a great use for smaller drives, as many ISOs can fit on a 2GB or smaller drive.
Step 1: Choosing an ISO
There’s no shortage of live CD software available for Linux. Here’s a list of top contenders:
Hiren’s Boot CD PE comes packed with goodies. It uses Windows 10 PE, a version of Windows intended for testing and system recovery. The PE stands for Preinstallation Environment. There are plenty of tools inside Hiren’s Boot CD PE for defragging, partitioning, backup, and more. The ISO requires 2GB of memory to run and supports UEFI booting.
SystemRescueCD boasts a hefty list of features. From rootkit and malware removal to data backup, partition repair, and lots of file system support, SystemRescueCD is a beefy live disk in a small package. It’s lightweight and versatile. For instance, you can boot into the command line, perfect for Linux, or into a GUI.
Need help troubleshooting? Ultimate Boot CD is a stellar pick. Comprised of diagnostic tools, it’s a solid pick for data recovery, testing peripherals such as RAM and CPU, managing BIOS, and system maintenance. The DOS-based UI may remind you of searching for books at the public library, but hey, Ultimate Boot CD is a well-rounded tool in a tiny package.
If you’re merely looking to repair your boot, boot-repair-disk is a solid choice. While it’s aimed at Linux distro boot repair, boot-repair-disk is compatible with select Windows systems. There’s a nice one-click repair mechanism, GRUB reinstaller, file system repair, and other awesome features.
Dedicated Linux Distro CD
In addition to this smattering of third-party tools, many Linux distros offer their own live CD ISOs. These serve as more complete general-purpose operating systems that may not come with recovery and system administration tools pre-installed, but they’re often easy to download as needed.
Another consideration for a boot disk is as a guest computer. These Linux distros usually include tools such as an office suite like LibreOffice, the Mozilla Firefox web browser, and other programs. You can merely boot into an operating system and use it as just that, a portable operating system.
Essentially, whichever tool you choose comes down to your needs.
Step 2: Writing Your ISO
Once you’ve picked your ISO of choice, it’s time to write it to media to create a bootable disk. Whether you use a spare USB drive or a blank CD/DVD is up to you, so long as it has sufficient space to hold your ISO. When it comes to creating a live CD, you will need a program capable of burning an ISO. UNetbootin is an excellent option with installers for Windows, macOS, and Linux.
Many Linux distros come with a tool for the job built-in, called Disk Image Writer (which is part of a system utility known as GNOME Disks). If you’re on the GNOME desktop, you can simply right-click your desired ISO, navigate to Open With Other Application, and select Disk Image Writer. You may even see Open With Disk Image Writer as the top option already.
Once open, select your media (USB drive, or blank DVD/CD). When you’ve picked the location to mount your ISO file for burning a live Linux CD, click Start Restoring.
Wait as the ISO is written to the disk (usually only a few minutes). After this finishes, you should have a live CD!
If you’re using a different program, the process may vary, but the general steps are the same.
- Select a source (the ISO you want to burn)
- Select a destination (burnable media)
- Mount the ISO to a disc
Step 3: Booting Into Your New Live CD
So long as you have your boot order in the correct sequence to boot from USB drives first, you should be able to launch your Linux live CD with ease. The process for this is rather easy, and just requires booting into your BIOS to edit the boot order.
How to edit the boot order varies by device, but you usually need to press one of the function keys along the top of your keyboard. You will sometimes see the key listed during boot, but on many devices, you will either have to search online, read the manual, or simply guess. Once you know the correct function key, you press it during the initial boot, before your operating system has loaded up.
What to Do With a Linux Live CD
Live CDs have many uses. You can carry one around as a sort of portable guest account for when you borrow a computer. They’re also awesome to have around when you need to troubleshoot, like when you’ve lost a password or are trying to recover data.
If you’ve opted for a general-purpose distro, then your live CD can be a good way to introduce others to Linux, even on their own PC!