[~Solved] bios+gpt+grub2 - Is it that weird of a combination?

zacariaz · 2012-08-17 15:23:02

Nothing much to it really.

Got an Asus eeepc 1015pem which I decided to throw my SSD in. The disk however is GPT, but hey, that shouldn't be a problem right?

Well, I've tried a number of ways now, without success I might add and am beginning to wonder, not least due to the fact that grub actually told me that I couldn't do what I wanted to do.

BTW, the 1015PEM is n ot EFI capable.

So if you got a minute to enlighten me, that'd be nice.

Best regards.

Last edited by zacariaz (2012-08-20 13:54:39)

zero_one · 2012-08-17 15:40:32

Check the Grub2 wiki. That combination works fine. I currrently have 2 machines running BIOS, GPT, and Grub2. Where are you getting hung up?

San2ban · 2012-08-17 15:47:26

I do not know about SSD, but this combination works beautifully on my SATA 160GB seagate HDD.
Just followed ArchWiki to set up
Are you manually formatting your GPT setup? Using gdisk or gparted? Have you created BIOS-boot partition?

[root@KRISHNA san2ban]# gdisk -l /dev/sda
GPT fdisk (gdisk) version 0.8.5

Partition table scan:
  MBR: protective
  BSD: not present
  APM: not present
  GPT: present

Found valid GPT with protective MBR; using GPT.
Disk /dev/sda: 312315562 sectors, 148.9 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): CECFDE10-048D-4CC1-9EF9-63A420410BE0
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 312315528
Partitions will be aligned on 2048-sector boundaries
Total free space is 8157 sectors (4.0 MiB)

Number  Start (sector)    End (sector)  Size       Code  Name
   1            2048            6143   2.0 MiB     EF02  BIOS_GRUB2
   2            6144         1048576   509.0 MiB   EF00  EFI System
   3         1054720         2103295   512.0 MiB   8300  ARCHLINUX_BOOT
   4         2103296         6297599   2.0 GiB     8200  ARCHLINUX_SWAP
   5         6297600        21657599   7.3 GiB     8300  ARCHLINUX_ROOT
   6        21657600       312315528   138.6 GiB   8300  ARCHLINUX_HOME

I have disabled EFI-boot in /etc/fstab, will remove this also, which was created during autoformat

zacariaz · 2012-08-17 16:02:28

Thank you very much for the feedback. It would seem I've missed some essentials.

In short, I've blanked out the SSD, created a GPT partition table with gdisk, including one single big partition, formated etx4.

Then the obvious next step is to install grub, but after trying both the bios and efi version, I'm out of ideas.

Anyhow, what I really wanted to know, before turning the net upsidedown, what if what I was trying to do was possible or not. For now that would seem to be the case, which is great and makes sense as it works perfectly well using syslinux.

Anyhow, got non arch related stuff to do. cya l8r.

zacariaz · 2012-08-17 16:08:19

Before I get going I just read a small bit and it would seem that what I want to do is in fact not possible and that I should use syslinux or something else. I'm not interested in a boot partition to be honest.

Please confirm.

best regards.

San2ban · 2012-08-17 16:49:40

Pl. see below info from ArchWiki

 BIOS systems

    GRUB(2) requires a 2 MiB "BIOS Boot Partition" (EF02 type code in gdisk and bios_grub flag in GNU Parted) in BIOS systems to embed its core.img file due to lack of post-MBR embed gap in GPT disks. Runtime GPT support in GRUB(2) is provided by the part_gpt module. See GRUB#GPT_specific_instructions for more information.

Since you do not use EFI, but BIOS, and GRUB2, BIOS BOOT partition is a must

San2ban · 2012-08-17 16:50:27

Pl. see below info from ArchWiki

 BIOS systems

    GRUB(2) requires a 2 MiB "BIOS Boot Partition" (EF02 type code in gdisk and bios_grub flag in GNU Parted) in BIOS systems to embed its core.img file due to lack of post-MBR embed gap in GPT disks. Runtime GPT support in GRUB(2) is provided by the part_gpt module. See GRUB#GPT_specific_instructions for more information.

Since you do not use EFI, but BIOS, and GRUB2, BIOS BOOT partition is a must

cfr · 2012-08-18 02:14:12

It isn't a "boot partition" in the usual sense if that's what you are thinking. You need it because GPT doesn't leave a "gap" the way MBR does so if you don't make room for it, GRUB can't find space to install to on the disk.

It isn't the sort of boot partition you mount at /boot and keep kernel images or grub.cfg in...

zacariaz · 2012-08-19 01:38:31

cfr wrote:

It isn't a "boot partition" in the usual sense if that's what you are thinking. You need it because GPT doesn't leave a "gap" the way MBR does so if you don't make room for it, GRUB can't find space to install to on the disk.
It isn't the sort of boot partition you mount at /boot and keep kernel images or grub.cfg in...

I kinda gathered that, but thank you for confirming it.

In any case, I know that syslinux works as I've used it in this way before, only I don't really care for syslinux as I find it kinda bothersome to configure in a way that suits me (honestly, I just don't wanna notice the boot loader.... at all!)

I suppose, come to think of it, that the real question is: Is there any good reason at all, not to convert to MBR and leave all the trouble behind?

ratcheer · 2012-08-19 12:24:25

I use MBR with GPT and grub2. The combination has never caused me any trouble at all. I don't know how to tell you how to fix your problems, I am just telling you that it does work.

My favorite reference site for gpt is: http://www.rodsbooks.com/gdisk/ This is the website of the man that wrote the gdisk program for maintaing gpt systems. It should tell you everything you need to get started and continue using gpt.

Tim

cfr · 2012-08-19 13:26:14

zacariaz wrote:

I suppose, come to think of it, that the real question is: Is there any good reason at all, not to convert to MBR and leave all the trouble behind?

Take a look at the wiki page on GPT and the wiki information on SSDs. My understanding is that GPT has several advantages even for HDD but that it is particularly recommended for SSD because it is better for the disk. (I don't have a SSD but I still decided the advantages of GPT were worth the trouble. On my mother's machine, I definitely wanted GPT as she's got a SSD.)

But, in the end, whether it is worth it is a matter of your weighing the pros and cons.

For what it's worth, I couldn't persuade my machine to boot in BIOS legacy mode with GPT no matter what I did. But mine is EFI capable and (after a lot of dead-ends) I managed to get that to work. If you're having problems, try googling for your firmware and see if anybody else has reported - or even solved - similar issues. That's how I finally found a work around for mine.

But first make sure that you've really followed the installation instructions on the wiki to the letter so that you can be sure that you really are experiencing something caused by e.g. buggy firmware if you think that's the problem.

Last edited by cfr (2012-08-19 13:27:25)

zacariaz · 2012-08-19 15:28:20

ratcheer wrote:

I use MBR with GPT and grub2. The combination has never caused me any trouble at all. I don't know how to tell you how to fix your problems, I am just telling you that it does work.
My favorite reference site for gpt is: http://www.rodsbooks.com/gdisk/ This is the website of the man that wrote the gdisk program for maintaing gpt systems. It should tell you everything you need to get started and continue using gpt.
Tim

As I understand it the grub 2 bootloader is simply to large to fit in what I suppose must be the protected mbr, which is the reason you need a separate partition. either that or I haven't got a clue. In any casse I will chekc you rlink out.

best regards.

Last edited by zacariaz (2012-08-19 16:35:08)

zacariaz · 2012-08-20 13:54:19

Gonna mark this thread solved now. I more or less get how bios+gtp is supposed to work with grub to, though I don't really care for it. I mean, syslinux don't need and extra 2MiB partition, so why should grub? Furthermore, I have trouble figuring out exactly how grub2 is set up in this matter.

In the en though, it don't need to be that complicated, I mean I don't really care about a boot menu and such. If I need advanced option, then I've got a bootable usb to help me.

I suppose what I'm trying to say here is issue solved, but if you know of a simple solution to the bios+gpt problem, apart from SYSLINUX obviously, then I'd like to know about it.

So long and thanks for all the fish!

zero_one · 2012-08-20 20:20:50

Hey zacariaz, just an overlooked question. Are you chrooting to /dev/sda before installing?

zacariaz · 2012-08-20 20:27:00

using the arch-chroot, if you're talking the base arch install, but otherwise I restart and login normally. Why is it important?

zero_one · 2012-08-20 20:33:23

zacariaz wrote:

using the arch-chroot, if you're talking the base arch install, but otherwise I restart and login normally. Why is it important?

As in,

# arch-chroot /new/root/dir/on/sda

# grub-install --directory=/usr/lib/grub/i386-pc --target=i386-pc --boot-directory=/boot --recheck --debug /dev/sda

# mkdir -p /boot/grub/locale

# cp /usr/share/locale/en\@quot/LC_MESSAGES/grub.mo /boot/grub/locale/en.mo

# grub-mkconfig -o /boot/grub/grub.cfg

I saw you listed the thread as solved. But, installing syslinx doesn't solve the grub-bios-gpt issue.

zacariaz · 2012-08-20 20:41:25

oh sorry, I thought it was another thread (slapping my self), but no, to be honest I didn't mark it completely as solved, only ~solved.

In any case the wiki clearly state that a 2 MiB boot partition is needed for grub to work in my situation and as I don't really want that and couldn't find instructions anyway, then the choice what obvious. Beside, I've solved the problems I've has with SYSLINUX.

zero_one · 2012-08-20 20:45:23

Seems like most people want to go the way of syslinux these days anyway. I personally don't use it. Coming from slackware i used the default LILO and when I switched to arch used Grub legacy.

Last edited by zero_one (2012-08-20 20:46:40)

zacariaz · 2012-08-20 20:55:06

Well I never really cared for lilo, not quite sure why, and as for grub legacy, it don't really work with GPT, not out of the box anyway.

GRUB2 is without a doubt the most functional bootloader out there, but it is not more user friendly, not for a distribution like arch at least, and the extra functionality... Well, who needs it?

Personally I don't even have a boot menu, I just don't need it and should something go wrong, I'm perfectly capable of fixing stuff using a bootable usb.

Initially I did decide on GRUB2, simply because it seem to be the recommendation, but at the end of the day, I'm actually kind of happy I couldn't get it to work. Made my life simpler in the long run I think.

cfr · 2012-08-20 22:44:52

For what it is worth, manually maintaining grub2's config file makes it a whole lot simpler and more obvious what's going on. Since Arch never regenerates grub.cfg automatically as other distros do, this also works just fine.

I guess grub2 is the obvious choice if you boot EFI mode since syslinux still can't support that. But it sounds like a nice option for BIOS mode.

zacariaz · 2012-08-21 11:22:39

cfr wrote:

For what it is worth, manually maintaining grub2's config file makes it a whole lot simpler and more obvious what's going on. Since Arch never regenerates grub.cfg automatically as other distros do, this also works just fine.
I guess grub2 is the obvious choice if you boot EFI mode since syslinux still can't support that. But it sounds like a nice option for BIOS mode.

Indeed, but after kernel 3.1 (I think) you don't really need a bootloader for EFI do you?

cfr · 2012-08-21 15:24:21

Isn't that true only if you only boot one OS in one configuration? I assume you still need something to get a choice?

zacariaz · 2012-08-21 15:27:22

cfr wrote:

Isn't that true only if you only boot one OS in one configuration? I assume you still need something to get a choice?

Can't say for sure, but I do believe that many, not most or all, EFIs provide some sort of menu or whatever.

In any case I don't really care as I've long since given Windows the finger and don't need multiple Linux systems on the same computer.

Arch Linux

#1 2012-08-17 15:23:02

[~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#2 2012-08-17 15:40:32

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#3 2012-08-17 15:47:26

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#4 2012-08-17 16:02:28

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#5 2012-08-17 16:08:19

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#6 2012-08-17 16:49:40

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#7 2012-08-17 16:50:27

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#8 2012-08-18 02:14:12

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#9 2012-08-19 01:38:31

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#10 2012-08-19 12:24:25

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#11 2012-08-19 13:26:14

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#12 2012-08-19 15:28:20

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#13 2012-08-20 13:54:19

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#14 2012-08-20 20:20:50

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#15 2012-08-20 20:27:00

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#16 2012-08-20 20:33:23

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#17 2012-08-20 20:41:25

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#18 2012-08-20 20:45:23

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#19 2012-08-20 20:55:06

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#20 2012-08-20 22:44:52

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#21 2012-08-21 11:22:39

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#22 2012-08-21 15:24:21

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

#23 2012-08-21 15:27:22

Re: [~Solved] bios+gpt+grub2 - Is it that weird of a combination?

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