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#1 2013-01-01 18:06:35

Evert7
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From: Lier, Belgium
Registered: 2012-02-18
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[SOLVED] EFI - No idea what to do

Hello everybody,

Yesterday I got my new PC ( i7 3770K, GTX660 Ti, ASRock Z77 Extreme4, 2x8GB Kingston PC17066 Beast RAM, ...) and of course I want to install Arch on it. More specifically, I want a pure EFI system (called efistub??) , which is also able to dual boot Windows 7 (needed for Adobe CS).

However, I have no idea what I should do. I don't seem to be able to create a UEFI-bootable USB. Documentation isn't as good as MBR. I tried a lot of things, but none of them worked. Can anybody please help me and give me some tips?

Thanks in advance, Evert.

Last edited by Evert7 (2013-01-02 20:13:51)

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#2 2013-01-01 18:50:55

cfr
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Re: [SOLVED] EFI - No idea what to do

If a CD isn't an option and you can't create the media for EFI boot you have several options:
1) using an older version of the install media as some people have had problems with EFI and the latest media (the October iso definitely works)
2) install booted in BIOS mode but set up as for EFI. You can do everything except setting up the boot loader/boot menu this way. You can then use any EFI bootable USB to boot in EFI mode and chroot to fix the boot loader/boot menu entries. (Maybe you can even avoid this if you place a suitable .efi in the default position but I haven't tried this and am not sure.)
3) use the archboot iso.

The wiki has a lot of information. If you want help, you need to explain what you've done, what you are trying to do and what error messages you are getting. Right now you are just asking to be walked through the install because "none of them worked" which says precisely nothing about what the problem might be.

Please see the link in my signature on how to ask a better question.


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#3 2013-01-01 18:58:46

JLloyd13
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Re: [SOLVED] EFI - No idea what to do

You want my advice? Ignore it. Efi is a massive pain in all cases I've delt with. Pretty much every efi motherboards with the possable exception of macs support bios booting either with MBR or GPT with a biosboot partition. The only disadvatage would be that you don't get the tiny bit faster boot time. Just my opinion though.

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#4 2013-01-01 19:00:28

cfr
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Re: [SOLVED] EFI - No idea what to do

Some firmware doesn't support EFI booting with a GPT map, though. For example, mine. Of course, I could use MBR but GPT does have advantages over MBR so I didn't want to.


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#5 2013-01-01 21:10:23

Evert7
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Re: [SOLVED] EFI - No idea what to do

cfr wrote:

The wiki has a lot of information. If you want help, you need to explain what you've done, what you are trying to do and what error messages you are getting. Right now you are just asking to be walked through the install because "none of them worked" which says precisely nothing about what the problem might be.

Please see the link in my signature on how to ask a better question.

My main problem is that I have no idea what to do. I know that my question is quite bad, I'll try to explain better:

First I'll explain my situation; I have no real linux system available (except for a RasPi) so I've made two USB sticks with Win32 Disk Imager.

Then; What I want is a dualboot system (or triple with an extra linux to try out new distros) with an Arch install and a Windows 7 install. I would like to use GPT and UEFI instead of MBR and BIOS (Windows won't allow any other combination). If there are any really big problems with those new technologies I consider switching to MBR and BIOS as well.

The first thing I tried is just what I'm used to (except for using gdisk instead of fdisk); plug in the USB and install Arch. I didn't see any real problems, but when booting no Arch appeared sad .
I then searched for a problem, and it turned out grub wasn't properly installed. I searched some more and the big bad UEFI mess appeared. So now I have no clue what to do, except for trying the October release like you suggested.

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#6 2013-01-01 22:09:39

cfr
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Re: [SOLVED] EFI - No idea what to do

Do you mean: (A) that you could not boot the USB you created? That is, you tried to boot it but "no Arch appeared"?

Or: (B) you booted the USB fine, maybe installed Arch according to the Beginner's Guide but then when you rebooted "no Arch appeared"?

If (A), did you check that the .iso download was not corrupt?

If (B), can you explain exactly what you *do* see? If you see an error message, what is it? If not, what do you see?

EDIT: If the problem is *just* that grub is not installed, all you need to do is fix that. What exactly did you do to install grub? Did the pacman step go OK? If so, the easiest thing is to get hold of any Linux distro you can boot in EFI mode. (Ubuntu comes to mind if you have a stick which is at least 2 G - it is easier to create their USB in Windows than it is in Linux.) Boot Ubuntu (or whatever), get a terminal, modprobe efivars and set up the chroot, chroot into your install and run grub-install to install grub to disk and set up the boot loader.

Last edited by cfr (2013-01-01 22:13:17)


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#7 2013-01-01 22:19:41

ronmon
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Re: [SOLVED] EFI - No idea what to do

I recently bought a new UEFI motherboard and an SSD. Since I migrated my current Arch over to the new drive I didn't have to do the entire installation. But I did make a UEFI bootable thumb drive from archlinux-2012.12.01-dual.iso to complete the job. You can find out how to make one here.

https://wiki.archlinux.org/index.php/UE … B_from_ISO

You might want to give that entire article a read.

The most complete information on UEFI that I have found, including dual booting, is here.

http://www.rodsbooks.com/efi-bootloaders/

There is no single place that I know of that takes you step by step through the entire process, so it took a while to piece it together. However, I ended up with a pure UEFI boot using rEFInd and efistub.

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#8 2013-01-01 23:30:41

cfr
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Re: [SOLVED] EFI - No idea what to do

I think part of the problem is that the OP is trying to create the USB from Windows due to lack of access to a Linux installation.

It occurs to me, though, that provided you have 2 USB ports (and in some cases even if you don't), you can boot from one USB key into the "live" Linux environment and then create a second EFI-bootable USB key from there. That is, you don't need to be booted in EFI mode to make the EFI-bootable key. In that case. those instructions should be available to you as you could create a BIOS-bootable key from Windows and then create the EFI-bootable key while booted from the first one.


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#9 2013-01-02 09:34:27

Evert7
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Re: [SOLVED] EFI - No idea what to do

cfr wrote:

It occurs to me, though, that provided you have 2 USB ports (and in some cases even if you don't), you can boot from one USB key into the "live" Linux environment and then create a second EFI-bootable USB key from there. That is, you don't need to be booted in EFI mode to make the EFI-bootable key. In that case. those instructions should be available to you as you could create a BIOS-bootable key from Windows and then create the EFI-bootable key while booted from the first one.

That's exactly what I'm doing now.
To answer your previous post; my problem is B, after booting to hard disk which should have Arh on it, nothing is being booted. It says: "Reboot and select proper Boot device or Insert Boot Media in selected Boot Device and press a key"

Right now I found a guide at overclockers.net, http://www.overclockers.com/forums/show … p?t=707382 (which is pretty old, but still)
I'm strugling with getting an uefi shell.

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#10 2013-01-02 14:04:48

ronmon
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Re: [SOLVED] EFI - No idea what to do

So it sounds like you have installed Arch (including efibootmgr and refind-efi) and now it won't boot? If that is the case, it is where I was when I had to boot off the USB stick in UEFI mode to make the installation bootable. You might want to look at this.

https://wiki.archlinux.org/index.php/Be … therboards

They do talk about using GRUB, but I am not using a boot loader except for efistub. The last little hurdle I had to jump to fix things was the efibootmgr command.

efibootmgr -c -g -d /dev/sda -p 2 -w -L "rEFInd" -l '\EFI\refindx64.efi'

I adapted the redundant and over-recursive directory scheme that most documentation recommends and simplified it. My EFI partition (/dev/sda2, which are the -d and -p options above) is mounted at /boot/EFI and looks like this:

0853 pts/3 ~
root@maxx # ls -l /boot/EFI/
total 16584
drwxr-xr-x 2 root root     4096 Dec 31 11:16 drivers
drwxr-xr-x 2 root root     4096 Dec 31 12:58 icons
-rwxr-xr-x 1 root root 10841058 Dec 31 16:47 initramfs-linux-fallback.img
-rwxr-xr-x 1 root root  2469705 Dec 31 22:50 initramfs-linux.img
-rwxr-xr-x 1 root root    13094 Jan  1 11:13 refind.conf
-rwxr-xr-x 1 root root      380 Jan  1 09:49 refind_linux.conf
-rwxr-xr-x 1 root root   123392 Dec 31 11:13 refindx64.efi
drwxr-xr-x 2 root root     4096 Dec 31 11:19 tools
-rwxr-xr-x 1 root root  3508832 Dec 31 16:47 vmlinuz-linux

Then, in refind.conf I set it up to use the kernel and image names that Arch uses. All I will have to do after a kernel update is copy them from /boot to /boot/EFI. The particular lines in refind.conf look like this.

scanfor manual

and

menuentry Arch {
    icon EFI/icons/os_arch.icns
    loader vmlinuz-linux
    initrd initramfs-linux.img
    options "root=/dev/sda3 ro vga=773"
}

menuentry ArchFallback {
    icon EFI/icons/os_arch.icns
    loader vmlinuz-linux
    initrd initramfs-linux-fallback.img
    options "root=/dev/sda3 ro vga=773"
}

Good luck.

Last edited by ronmon (2013-01-02 14:21:35)

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#11 2013-01-02 15:14:24

cfr
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Re: [SOLVED] EFI - No idea what to do

If you are having trouble with efibootmgr try copying grubx64.efi to /boot/efi/EFI/boot/bootx64.efi.

If you are using rEFInd, copy refindx64.efi to /boot/efi/EFI/boot/bootx64.efi.


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#12 2013-01-02 16:21:05

srs5694
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Re: [SOLVED] EFI - No idea what to do

Evert7 wrote:

I'm strugling with getting an uefi shell.

Do you have a CD drive? If so, the CD image file for rEFInd (available here) includes an EFI shell. Even if you don't have a CD drive, you could download that image file, mount it as a loopback image, and copy its contents to a FAT partition on a USB flash drive to get a bootable rEFInd with EFI shell.

ronmon wrote:

I adapted the redundant and over-recursive directory scheme that most documentation recommends and simplified it. My EFI partition (/dev/sda2, which are the -d and -p options above) is mounted at /boot/EFI

The EFI spec is quite clear in stating that boot loaders should reside in subdirectories of the ESP's "EFI" directory, as in EFI/BOOT, EFI/arch, EFI/Microsoft, and so on. The directory structure you get in Linux is not recursive (much less "over-recursive"), and although it's got some repeating elements, these are a consequence of the traditional /boot/efi mount point. If you mount the ESP at /boot (as many Arch users do), you'd get /boot/EFI/arch, /boot/EFI/BOOT, and so on.

Placing EFI boot loaders in the ESP's root, as you seem to have done, will work, but it also violates the EFI spec. Personally, I'm willing to go that far for Linux kernels when I mount the ESP at /boot, but not for other boot loaders.

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#13 2013-01-02 17:04:17

ronmon
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Re: [SOLVED] EFI - No idea what to do

^^
You're the guru, so I'll take your word for it. Thanks for the clarification and the great documentation on your web site. The over-recursiveness I referred to were recommendations I saw to use /boot/EFI/efi/... and the like, which seemed redundant (I do not use PIN 'numbers' on ATM 'machines'). It is unlikely that this machine will ever have more than one distro on it at a time and it will certainly _never_ have a Microsoft OS installed, so I simplified it for my purposes. Like I said, it is what worked for me.

So in other words, Evert7, ignore everything I said, listen to the experts, and good luck.

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#14 2013-01-02 20:02:42

Evert7
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Re: [SOLVED] EFI - No idea what to do

Update! I got a working system. It's not a real pure EFI system afaik, but it works. After trying a lot (read: placing the shellx64.efi file in every map possible on my USB) I got into an UEFI shell which was enough to get things rolling. I now boot in grub (with grubx64.efi) and from there things are pretty familiar. I will do some more research before trying to make it pure EFI, so I won't have to come back here all the time. I'm planning to read all your web pages (http://www.rodsbooks.com/efi-bootloaders/index.html afaik) about EFI before I proceed.

Much thanks for all your help and patience.

PS: @srs5694: I can't donate any money, but if you really want I could make you a nicer site smile

Last edited by Evert7 (2013-01-02 20:08:24)

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#15 2013-01-02 20:48:04

cfr
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Re: [SOLVED] EFI - No idea what to do

Note that that *is* pure EFI. You are just using a boot loader (grub). You're not using the EFI stub ability of recent kernels but that doesn't mean you aren't using pure EFI. (Actually, I don't think you can boot in impure EFI mode - at least, not that I know of : either it is BIOS legacy or EFI. Not sure about "hybrids" though as I don't really understand those.) Until extremely recently this just was how you booted in EFI mode if you did it at all. (At least, other distros had a version of grub legacy which did EFI but grub2 was the unpatched loader which worked for EFI. And before anybody says, I know there are others. But this was the "standard" recommendation for EFI.)

So... congratulations on your pure EFI booting!

Last edited by cfr (2013-01-02 20:49:09)


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#16 2013-01-04 18:35:47

ANOKNUSA
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Re: [SOLVED] EFI - No idea what to do

@cfr: Some newer, Intel-based, UEFI-capable motherboards have their own native boot selection menu that can be accessed/modified via the board's BIOS setup screen, and entries can be added using efibootmgr.  That's how I boot my machine: I have Win7 installed on one disk with its own bootloader, and Arch on another using efistub.  By default, the machine boots straight to Arch unless I hit F12 and interupt it, and tell it to boot Windows.  Hence, no need to install grub/syslinux/rEFInd/whatever to boot or chainload anything, or waste (an admittedly trivial amount of) time loading a menu that then loads yet another program; the post process simply jumps straight to booting the first entry on the list, which is controlled directly by the machine.  That may be what Evert7 is getting at. 

@Evert7: If my guess on this is correct, the Arch wiki entries on UEFI/UEFI Bootloaders contain information on how to achieve that.  It's kinda tedious--you'll likely need to do a bit of trial-and-error--but once it's done, you shouldn't ever have to modify it unless you uninstall Arch.

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#17 2013-01-04 22:50:33

cfr
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Re: [SOLVED] EFI - No idea what to do

I know - I just meant that it is not less pure EFI because you don't use that mechanism. (I can't actually add the entries via my BIOS setup but if I add them via efibootmgr they show up there and can be re-ordered and F12 gets the menu in my case, too.

Note, too, that rEFInd is a boot manager whereas grub and syslinux are boot loaders. I'm not quite sure of what this means in technical terms, though.

If I put a suitable .efi at /boot/efi/EFI/boot/bootx64.efi, my system will boot that by default if it is set to boot from the HDD by default. I use this as a fallback in case I lose the additional entries in the EFI boot menu. But you can also use this to e.g. boot Arch by default. I guess that you have something like that set up?


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#18 2013-01-04 23:10:55

srs5694
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Re: [SOLVED] EFI - No idea what to do

cfr wrote:

Note, too, that rEFInd is a boot manager whereas grub and syslinux are boot loaders. I'm not quite sure of what this means in technical terms, though.

Just this:

  • A boot manager presents a list of boot options to users, or otherwise enables users to select which OS to boot. It's basically a user interface and selection mechanism.

  • A boot loader loads an OS kernel, and perhaps associated extra data such as an initial RAM disk, into memory and transfers control to it. There's little or no user interface involved, at least not necessarily. (All but the most primitive boot loaders will have some sort of feedback mechanism to tell users about errors, though.)

You're correct that rEFInd is a boot manager, as are rEFIt and gummiboot. Most EFI implementations also include their own boot managers, although even the best of the ones I've seen are painfully awkward. GRUB and SYSLINUX are, as you say, both boot loaders; but GRUB is also a boot manager. (I believe this is also true of SYSLINUX, although I'm only passingly familiar with it.) In fact, the vast majority of Linux boot loaders in the BIOS world also include boot manager features, so Linux users have traditionally used the two terms interchangeably. EFI's design makes it desirable to separate the two functions into two programs, enabling you to mix and match as you see fit. For instance, you can use the EFI stub loader (a boot loader with no boot manager features) with the firmware's boot manager, with rEFInd, with gummiboot, or even with an EFI shell (which can be thought of as a very free-form sort of boot manager). If you don't like the EFI stub loader, you can use any of those boot managers with ELILO instead.

Putting both boot manager and boot loader functionality in one program, as GRUB does, is convenient but limiting, since it restricts your options for customization should you want or need to change something in a way that the program doesn't support. In the case of GRUB, you also wind up with a lot of functionality that you probably don't need, like the ability to load GNU HURD kernels. On the face of it this doesn't do any real harm, but the extra complexity is likely to result in extra bugs. It's taken the GRUB 2 developers years to get to a point of tolerable stability, whereas the kernel EFI stub developers produced something usable in a matter of weeks to months.

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#19 2013-01-04 23:51:17

cfr
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Re: [SOLVED] EFI - No idea what to do

Thanks for the clarification. I didn't realise Linux boot loaders also served/had features of boot managers and knowing that makes things clearer. I've always had grub present a menu, for example, so presumably that is boot-manager behaviour?

There's no way to, for example, boot an .iso without something like grub, though, right? I currently have rEFInd as primary boot manager, if one can say that, and then have grub as one entry there so that I can get the full grub menu which includes an .iso if I want it. (Actually, it includes 2 but only one actually works.)


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#20 2013-01-05 00:21:59

WonderWoofy
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Re: [SOLVED] EFI - No idea what to do

@ANOKNUSA
I too thought at first that it was simply a "waste of time" to first have my machine load a boot manager/loader which then booted the kernel stub loader.  But then I realized what a PITA it is to change kernel parameters on the fly.  When I was using a sole efibootmgr entry, I would achieve this by using an entry for the uefi shell, then type it all in by hand (the trial and error process you mentioned above ensured that my necessary parameters are committed to memory). 

But since then (and a bit more putzing about with stuff), I discovered gummiboot has an option for no timeout.  By setting it this way, there seems to be no discernible difference between loading gummiboot -> stub loader and simply the stub loader alone.  I imagine this is partially because I use a SSD, but also because the binary is so damn small @ 77KB.  So if I want to get to the gummiboot menu, I just hold down the space bar, and I get the menu.  Then you can press 'e' to edit the parameters.

The point at which I decided that I needed (not just wanted) something more than an efibootmgr entry was when I accidently reset my bios and all my entries disappeared.  So now I keep gummiboot as \EFI\boot\bootx64.efi just in case.

Srs5694 also pointed out to me that his rEFInd has a text only mode that is pretty neat.  But I think that rEFInd's configuration is too complicated for such a thing.  If I wanted a pretty interface then it would be different, as more configuration would be expected.  (No disrespect srs5694, your rEFInd is great, its just not what I am looking for personally.)

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#21 2013-01-05 01:46:39

cfr
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Re: [SOLVED] EFI - No idea what to do

Does the efi boot menu entry for gummiboot actually serve a purpose in that case? I mean if it will fall back to that anyway because gummiboot is at the default location. I've been wondering this myself since I currently have rEFInd and grub as entries in the menu and also have rEFInd in the fallback position. Since rEFInd is also the default entry in the menu, I wonder it would be all the same to just have the grub menu entry. (I'm not likely to do this because I like the completeness this way and I've had enough problems booting to think multiple routes a Good Thing. But hypothetically...)


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#22 2013-01-05 03:14:58

WonderWoofy
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Re: [SOLVED] EFI - No idea what to do

I think it is pretty much the same (same result anyway).  I have gummiboot in the default position, just in case all my entries disappear.  But I actually use a gummiboot efibootmgr entry.  This is because I disabled the ability to boot from the harddrive itself and have a password for the bios.  I figure in this way, one is forced to boot from this one entry (though I also have an entry to the UEFI Shell that is active, but only those two).  Then from the gummiboot menu, you can boot Arch with the normal kernel or with the ck kernel (default), and I also have access from here to the UEFI Shell.  I guess that is just in case I forget I wanted to go the the shell I don't have to reboot to get there.

But I think that the answer to your question is, no there is no advantage, I think it is personal preference.  I no longer have the direct Arch boot manager entries there anymore though.

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#23 2013-01-05 03:39:59

srs5694
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Re: [SOLVED] EFI - No idea what to do

cfr wrote:

Thanks for the clarification. I didn't realise Linux boot loaders also served/had features of boot managers and knowing that makes things clearer. I've always had grub present a menu, for example, so presumably that is boot-manager behaviour?

Correct; if you see a menu, that's a boot manager. (ELILO is a halfway case; it gives you boot options, but only between different Linux kernels.) The program may also include boot loader features (as GRUB does). If you don't understand the architecture, it can be hard to tell the difference sometimes. For instance, you can boot GRUB->kernel or rEFInd->kernel, which seem like identical boot paths but for the first program; but technically, in the first path GRUB is both the boot manager and the boot loader, whereas in the second path rEFInd is just a boot manager and the kernel includes its own boot loader (the EFI stub loader).

There's no way to, for example, boot an .iso without something like grub, though, right? I currently have rEFInd as primary boot manager, if one can say that, and then have grub as one entry there so that I can get the full grub menu which includes an .iso if I want it. (Actually, it includes 2 but only one actually works.)

That depends. Given the right driver (which doesn't yet exist), rEFInd could launch boot programs off an image file. You'd just need an EFI filesystem driver that's capable of mounting an image file. GRUB can do this itself -- that's one of the many GRUB features that's vital if you need it and bloat if you don't. In terms of the boot loader vs. boot manager issue, though, it's really central to neither category and could arguably be included in either, depending on the details of how it works.

cfr wrote:

Does the efi boot menu entry for gummiboot actually serve a purpose in that case? I mean if it will fall back to that anyway because gummiboot is at the default location.

If you're using the fallback filename (EFI/BOOT/bootx64.efi), and if you're using precisely one boot program, then there's not much point in creating an NVRAM entry for that boot program with efibootmgr. Having such an entry might make sense if you want to have multiple NVRAM entries, though. For instance, suppose you normally want to use gummiboot, but you want the option to launch rEFInd via the firmware's own boot manager. In that case, you'd want two NVRAM entries, since the firmware doesn't usually give an option to use the fallback filename. There's nothing preventing you from entering the fallback filename in the firmware, so you could store gummiboot as EFI/BOOT/bootx64.efi, enter it in the firmware as the first boot program, and enter rEFInd (under EFI/refind/refind_x64.efi or whatever) as a secondary entry.

Of course, you can configure gummiboot to launch rEFInd (or vice-versa), so in day-to-day use there won't really be much benefit to creating those NVRAM entries at all. It might be handy, though, in case a new version of a program has a bad bug. For instance, if you update gummiboot and the new version hangs, having rEFInd in your firmware's boot manager will enable you to boot via rEFInd. If you just had gummiboot as EFI/BOOT/bootx64.efi and no NVRAM entries, you'd need to break out a boot loader on a bootable CD or USB flash drive to get your computer to boot.

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#24 2013-01-06 00:34:08

cfr
Member
From: Cymru
Registered: 2011-11-27
Posts: 7,130

Re: [SOLVED] EFI - No idea what to do

Thanks for the very detailed and helpful explanations - I definitely appreciate you both taking the time to post answers to my questions.


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