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In this video, you learn how to work with UEFI from Linux.

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So in Linux, there is the EFI boot manager, and that makes managing UEFI boot targets

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possible from within the operating system.

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Apart from the EFI boot manager, you normally can also crash a key.

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That's to maintain some BIOS compatibility and to make sure that you can also decide

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what you want to boot if you cannot access the operating system.

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But EFI boot manager is a nice utility.

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It will show you current targets using EFI boot manager without any arguments.

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And the active boot entries is marked with an asterisk.

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Use EFI boot manager minus V for more details, and you can force the system to boot into

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another entry the next time it is started by using the minus N option.

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For instance, if 2C is the entry that you identified, you can use EFI boot manager minus

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N 2C.

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And alternatively, you can also press one of the typical hotkeys.

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Either Escape, F2, F10 or F12 are normally used and should get you into a boot menu.

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Let me show you.

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Okay, let's start with LSBOK.

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LSBOK is showing all block devices, including SCA1, which is mounted on slash boot slash EFI.

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So in this boot EFI, what do you find?

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Well, you find the EFI subdirectory, and there you will find everything, everything that's related.

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Most important, the CentOS directory, which contains the CentOS information.

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And here we have the boot information, all nicely readable in files.

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Now EFI boot MGR for EFI boot manager is showing all the different EFI options that are available.

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So you can see that the current boot is 0004, and if I wanted to boot into something else,

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then I would use EFI boot manager minus N 0001, for instance.

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Now everything that we see right here doesn't make too much sense, but we can give it a try.

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EFI boot manager minus N 2C, no, not 2C, EFI boot manager minus N 0001.

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And there you can see boot next is 0001.

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All right, I'm going to reboot.

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And while rebooting, I have pressed escape, and while pressing escape,

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I'm getting access to the boot manager menu.

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That is a hard override.

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So you can use EFI boot manager and wait until it has booted in the new target,

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or hit the right key at the right moment to get where you want.

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Well, I want to get back to CentOS stream because I have no intention of booting from a CD.

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With EFI boot manager, that is a utility that you can use to boot whichever image is available from the UEFI boot menu.