In this article, we will look into the difference between legacy GRUB and GRUB2 Boot Loader but before that let me ask you a quick question - Do you know what was the main problem with the legacy GRUB Bootloader which later resulted the creation of GRUB2 ? Well, there were many problems in the original GRUB but the main problem was it has becoming incredibly difficult to maintain due to messy code and multiple System Failures. It has been extended many times beyond the original scope due to multiple feature requests till it reached to a point where it cannot be extended any further.
So the need of the hour was to rethink and redesign the whole framework which ultimately resulted in the creation of GRUB2. So, in terms of design both are actually very different. We will see all the important differences between them in below section. More about GRUB Bootloader.
Differences between GRUB and GRUB2 Boot Loader
- It is known as Grand Unified Bootloader or legacy GRUB.
- It is the old Boot Loader.
- Used in older versions of RHEL/CentOS.
- Legacy GRUB ended at version 0.97 in 2005.
- It is configured through /boot/grub/grub.conf file.
- GRUB does not understand disk names like sda or vda.
- Changes in Boot Loader Configuration file can be done manually from the file.
- It has two main configuration files - menu.lst and grub.conf.
- Less user friendly and there is a chance of error due to manual configuration.
- Limited Graphical Capabilities.
- No option of creating any custom menu.
- Limited support of LVM and RAID Devices.
- In GRUB, partition number starts with 0.
- GRUB legacy is unable to boot on Systems without the /boot/ directory.
- Limited Features and less reliable.
- It uses more Programmatic Approach.
- It is the new Boot Loader.
- All the latest versions of Ubuntu contains GRUB2.
- GRUB2 is version 1.99 and up.
- It is configured through /etc/default/grub file.
- GRUB2 fully understand disk names like sda or vda.
- Changes in Boot Loader Configuration file done through grub2-mkconfig command.
- It has only one main configuration file namely grub.cfg.
- More user friendly and less prone to errors.
- Provides Extensive Graphical Capabilities.
- User has the choice to create their own custom menu.
- Supports LVM and RAID Devices.
- In GRUB2, partition number starts with 1.
- GRUB2 is able to boot on Systems without the /boot/ directory.
- It has multiple features and provides more reliability.