quick-docs/modules/ROOT/partialsdelete/2delete-proc_installing-grub2-on-bios-system.adoc

[[installing-grub-2-on-a-bios-system]]
= Installing GRUB2 on a BIOS system

Normally, *GRUB2* will be installed and set up by the installer, *Anaconda*, during the installation process. You will probably never have to deal with manual installation of *GRUB2*. However, in certain situations , you will want to install *GRUB2* manually, especially if you need to repair the existing *GRUB2* installation or you want to change its configuration.

This procedure shows the steps to install *GRUB2* on your _Master Boot Record_ (MBR) of your primary hard disk.

.Before you start

* Make sure you have the the *GRUB2* packages and the _os-prober_ package installed in your system.
+   
----
$ dnf list installed | grep grub
----

* To automatically collect information about your disks and operating systems installed on them, the `os-prober` package needs to be installed on your system.

.Procedure

. List block devices available on the system.
+
----
$ lsblk
----  

. Identify the primary hard disk. Usually, it is the `sda` device.

. Install *GRUB2* in the MBR of the primary hard disk.
+
----
# grub2-install /dev/sda
----

. Create a configuration file for *GRUB2*.
+
----
# grub2-mkconfig -o /boot/grub2/grub.cfg
----

. Reboot your computer to boot with the newly installed bootloader.

.More information

* The `grub2-mkconfig` command creates a new configuration based on the currently running system. It collects information from the `/boot` partition (or directory), from the `/etc/default/grub` file, and the customizable scripts in `/etc/grub.d/`. 

* The configuration format is changing with time, and a new configuration file can become slightly incompatible with the older versions of the bootloader. Always run `grub2-install` before you create the configuration file with `grub2-mkconfig`.

* In Fedora, it is generally safe to edit `/boot/grub2/grub.cfg` manually. *Grubby* in Fedora patches the configuration when a kernel update is performed and will try to not make any other changes than what is necessary. Manual changes can be overwritten with `grub2-mkconfig` when the system gets upgraded with *Anaconda*. Customizations placed in `/etc/grub.d/40_custom` or `/boot/grub2/custom.cfg` files will survive running the `grub2-mkconfig` command.
Partly modularize content 2017-12-12 16:56:25 +00:00			`[[installing-grub-2-on-a-bios-system]]`
Fixed Bootloading w/ Grub. 2018-01-20 17:59:12 +00:00			`= Installing GRUB2 on a BIOS system`
Partly modularize content 2017-12-12 16:56:25 +00:00
			`Normally, GRUB2 will be installed and set up by the installer, Anaconda, during the installation process. You will probably never have to deal with manual installation of GRUB2. However, in certain situations , you will want to install GRUB2 manually, especially if you need to repair the existing GRUB2 installation or you want to change its configuration.`

			`This procedure shows the steps to install GRUB2 on your _Master Boot Record_ (MBR) of your primary hard disk.`

			`.Before you start`

Small update (on reviewed grub articles) for consistency/style guidelines 2023-01-30 12:36:20 +00:00			`* Make sure you have the the GRUB2 packages and the _os-prober_ package installed in your system.`
Partly modularize content 2017-12-12 16:56:25 +00:00			`+`
			`----`
			`$ dnf list installed \| grep grub`
			`----`

			* To automatically collect information about your disks and operating systems installed on them, the `os-prober` package needs to be installed on your system.

			`.Procedure`

			`. List block devices available on the system.`
			`+`
			`----`
			`$ lsblk`
			`----`

			. Identify the primary hard disk. Usually, it is the `sda` device.

			`. Install GRUB2 in the MBR of the primary hard disk.`
			`+`
			`----`
Fixed Bootloading w/ Grub. 2018-01-20 17:59:12 +00:00			`# grub2-install /dev/sda`
Partly modularize content 2017-12-12 16:56:25 +00:00			`----`

Reviewed partial proc_installing-grub2-on-bios-system.adoc (part of #522) 2023-01-12 16:18:52 +00:00			`. Create a configuration file for GRUB2.`
			`+`
			`----`
			`# grub2-mkconfig -o /boot/grub2/grub.cfg`
			`----`

Partly modularize content 2017-12-12 16:56:25 +00:00			`. Reboot your computer to boot with the newly installed bootloader.`

			`.More information`

Fixed Bootloading w/ Grub. 2018-01-20 17:59:12 +00:00			* The `grub2-mkconfig` command creates a new configuration based on the currently running system. It collects information from the `/boot` partition (or directory), from the `/etc/default/grub` file, and the customizable scripts in `/etc/grub.d/`.

			* The configuration format is changing with time, and a new configuration file can become slightly incompatible with the older versions of the bootloader. Always run `grub2-install` before you create the configuration file with `grub2-mkconfig`.
Partly modularize content 2017-12-12 16:56:25 +00:00
Fixed Bootloading w/ Grub. 2018-01-20 17:59:12 +00:00			* In Fedora, it is generally safe to edit `/boot/grub2/grub.cfg` manually. Grubby in Fedora patches the configuration when a kernel update is performed and will try to not make any other changes than what is necessary. Manual changes can be overwritten with `grub2-mkconfig` when the system gets upgraded with Anaconda. Customizations placed in `/etc/grub.d/40_custom` or `/boot/grub2/custom.cfg` files will survive running the `grub2-mkconfig` command.