Sometimes things go wrong, even on Linux systems, and you need a way to get your computer back to full functionality. On Windows, Safe Mode is usually the first choice to get back in and fix a problem. However, on Linux, there really isn’t a direct counterpart.
On most Linux distributions i, the solution involves using a Live CD to access files on your hard drive or even using a chroot. Ubuntu has come up with a clever solution in recovery mode. It lets you perform several key recovery tasks, including booting into a root terminal to give you full access to fix your computer.
Note: this will only work on Ubuntu, Mint, and other Ubuntu-related distributions.
Boot to Recovery Mode in Ubuntu
As you’re booting your computer, wait for the manufacturer logo to flash from the BIOS. If your computer boots too quickly, you’re going to need to do this immediately after powering it on. Quickly press either the Shift or Escape key. On newer computers, it’s probably Escape. The timing has to be near perfect on some computers, so you may have to press it repeatedly. If you miss the window, reboot and try again.
With any luck, you’ll arrive at Ubuntu’s GRUB boot menu. Just below your regular boot option, you’ll see an entry for “Advanced Options.” Select it and press Enter.
GRUB will take you to a new menu. Toward the bottom you’ll see one of the entries with “Recovery” listed in parentheses.
You’ll arrive on a simple screen with a blue background and a box containing a series of recovery options. This is the main recovery menu for Ubuntu; it allows you to do many of the common tasks required to fix a broken system.
Understanding Recovery Options
As you can tell, you now have seven options to help recover Ubuntu. Depending on the issue you’re facing, you’ll want to choose the right one for your needs.
Each option does the following:
- Resume – If you somehow got to this menu accidentally, just use “resume” to continue booting normally.
- Clean – If you’re have space issues, opt for the “clean” option. It helps you free up valuable space to avoid a variety of system glitches.
- Dpkg – If you’re installing a new package and something went wrong, it can cause Ubuntu not to work properly. Use “dpkg” to try to repair any broken packages.
- Fsck º While it won’t always work, “fsck” is useful in troubleshooting hard drive issues. You can also use it to configure graphics drivers. If you suspect your hard drive may be corrupted or failing, use this tool.
- Grub – This is used just to automatically update the installed Grub bootloader.
- Network – If you’re having network issues, use the “network” option to help set things up again. Since networking is usually disabled unless you manually set it up, this can help with the process.
- Root – This is for more advanced troubleshooting. As you may notice, the Recovery Menu opens the system in a read-only state. The root tool helps you get write access (more on that below).
- System-summary – Get a basic overview of your system. In most cases, this isn’t the most useful option unless you want to ensure Ubuntu is recognizing different parts of your system.
The Root Terminal
Many problems can only be solved as root, and they require more manual intervention than what the default options in the recovery menu provide. When it looks like you’re dealing with one of these cases, select “Drop to root shell prompt” to boot into a root terminal.
As soon as you select it, you’ll see the bottom of your screen switch to a terminal and log in as root. Before you can do much, you’re going to need to remount the root partition of your drive. By default, it’s mounted read-only for safety purposes, but you’ll probably need to modify something to fix whatever issue’s going on. To remount it with write permissions, run the following command.
If you have additional partitions you need to work on, you’ll need to remount them as well. That includes when your “/home” directory is on a separate partition. You can remount them all at once simply with:
Now you’re ready to dig around in your system and resolve the problem that’s preventing you from booting normally. You’ll have access to everything on your system as root, so be careful not to damage anything in the process. Making backups, even just copies of the files you modify, is a great idea. Once you’ve uncovered and remedied the problem, reboot your system and boot normally.
Can’t Access GRUB Boot Menu
If for any reason you can’t access Ubuntu’s GRUB boot menu, you won’t be able to boot into recovery mode in Ubuntu. This usually means the bootloader and/or your Ubuntu system has been corrupted somehow. The easiest solution is to reinstall Ubuntu using a Live CD. There are a variety of reasons to have a Live CD on hand, and this is just one of them.
This method allows you to usually keep your files (as long as the hard drive isn’t corrupted beyond use). Plus, you’ll be able to repair whatever is going on with a fresh installation.
In most cases, booting into recovery mode in Ubuntu should be your first step for troubleshooting many issues you encounter. And, hopefully, you won’t need to reinstall Ubuntu at all.