How To Fix Ubuntu 18.04 Boot Hangs Indefinitely on Start Job for AppArmor Initialization

If you’re an Ubuntu 18.04 user and you’ve encountered a boot hang issue with the message “A start job is running for AppArmor initialization”, you’re not alone. This problem can be frustrating, but fortunately, there are ways to fix it. In this article, we’ll guide you through the process step by step.

Understanding the Issue

Before we delve into the solution, it’s important to understand the problem. AppArmor is a Linux kernel security module that allows the system administrator to restrict programs’ capabilities with per-program profiles. Sometimes, due to various reasons like system updates, configuration changes, or software conflicts, the AppArmor service might cause the system to hang during boot.

Accessing the GRUB Boot Menu

The first step to resolve this issue is to access the GRUB boot menu. To do this:

1. Reboot your machine.
2. Hold the Shift key as soon as you pass the BIOS logo. This should bring up the GRUB boot menu.

Entering Recovery Mode

Once you’re in the GRUB boot menu:

1. Select “advanced options” and hit Enter.
2. Select the option with “(recovery mode)” in front of it and hit Enter.

You should now be in recovery mode.

Dropping to Root Shell Prompt

In recovery mode:

1. Wait until the machine boots and another menu appears.
2. Choose the option with “drop to root shell prompt” and hit Enter.
3. Press Enter when it says “press Enter for maintenance.”

You should now be at the command prompt.

Disabling the AppArmor Service

At the command prompt:

1. Enter the following command to give read and write access to your system:

   mount -o rw,remount /

   The mount command is used to mount filesystems. The -o option allows you to specify several system options. In this case, rw stands for read-write and remount tells the system to remount the filesystem.
2. Disable the AppArmor service by entering the following command:

   sudo systemctl disable apparmor.service

   The systemctl command is used to control the systemd system and service manager. disable is an option that prevents the service from starting at boot.
3. Reboot your system.

If everything goes as planned, your system should now boot normally.

Alternative Method

If you’re unable to access recovery mode due to the same issue, you can try an alternative method:

1. At the GRUB menu, press “e” to edit the boot options.
2. Move the cursor after the last character in the last options line and press Enter to start a new line.
3. Add “systemd.mask=apparmor.service” with no spaces and then press F10 to boot the system.

The systemd.mask= option is a way to prevent a service from starting, similar to the disable option in systemctl.

Re-enabling AppArmor

Once your system is back to normal, you can enable the AppArmor service again for security purposes. To do this, run the following command in the terminal:

sudo systemctl enable apparmor.service

This command will enable the AppArmor service to start at boot.

Conclusion

While boot hang issues can be frustrating, they are often solvable with a bit of patience and the right steps. We hope this guide has helped you resolve the “A start job is running for AppArmor initialization” issue on Ubuntu 18.04. If you’re still experiencing problems, don’t hesitate to seek help from Ubuntu’s community forums.