In this video, you learn how to work with UEFI from Linux.
So in Linux, there is the EFI boot manager, and that makes managing UEFI boot targets
possible from within the operating system.
Apart from the EFI boot manager, you normally can also crash a key.
That's to maintain some BIOS compatibility and to make sure that you can also decide
what you want to boot if you cannot access the operating system.
But EFI boot manager is a nice utility.
It will show you current targets using EFI boot manager without any arguments.
And the active boot entries is marked with an asterisk.
Use EFI boot manager minus V for more details, and you can force the system to boot into
another entry the next time it is started by using the minus N option.
For instance, if 2C is the entry that you identified, you can use EFI boot manager minus
N 2C.
And alternatively, you can also press one of the typical hotkeys.
Either Escape, F2, F10 or F12 are normally used and should get you into a boot menu.
Let me show you.
Okay, let's start with LSBOK.
LSBOK is showing all block devices, including SCA1, which is mounted on slash boot slash EFI.
So in this boot EFI, what do you find?
Well, you find the EFI subdirectory, and there you will find everything that is related.
Most important, the CentOS directory, which contains the CentOS information.
And here we have the boot information, all nicely readable in files.
Now EFI boot MGR for EFI boot manager is showing all the different EFI options that are available.
So you can see that the current boot is 0004, and if I wanted to boot into something else,
then I would use EFI boot manager minus N 0001, for instance.
Now everything that you see right here doesn't make too much sense, but we can give it a try.
EFI boot manager minus N 2C, no, not 2C, EFI boot manager minus N 0001.
And there you can see boot next is 0001.
All right, I'm going to reboot.
And while rebooting, I have pressed escape, and while pressing escape,
I'm getting access to the boot manager menu.
That is a hard override.
So you can use EFI boot manager and wait until it has booted in the new target,
or hit the right key at the right moment to get where you want.
Well, I want to get back to CentOS stream because I have no intention of booting from a CD.
With EFI boot manager, that is a utility that you can use to boot whichever image is available from the UEFI boot menu.