Arch Linux

Smoerrebroed

Member

From: Germany

Registered: 2011-07-24

Posts: 110

[SOLVED] Arch/GRUB/GPT on USB 3.0 Stick

Hi All,

I am currently trying to master installing Arch on a Kingston Traveller DT Ultimate G2 USB 3.0 running on a HP EliteBook 840 G3. Customarily, I have worked through the Arch Installation Guide, taking into account the special remarks for Installing Arch Linux on a USB key.

The USB key is GPT partitioned as follows:

Partition 1: 512 MB, EFI, mounted at /boot
Partition 2: all remaining space, ext4, mounted at /

Those partitions are correctly entered in /etc/fstab, using UUID as reference.

Installing and configuring grub (with the --removable) option gave no errors, and I have also moved the block hook of the initial ram disk right after udev, recreating the ram disk afterwards.

Now, when I start the machine and go to the boot menu, I can select the USB key for UEFI booting. I am presented with the grub menu and can select Arch Linux for booting. Confirming my choice, I get the following output:

Loading Linux linux ...
Loading initial ramdisk ...

starting version 232
ERROR: device 'UUID=...' not found. Skipping fsck.
mount: can't find UUID=...
You are now being dropped to an emergency shell.
sh: can't access tty; job control turned off

[rootfs ]# [   16.863297] sd 3:0:0:0: [sdb] No Caching mode page found
[   16.863297] sd 3:0:0:0: [sdb] Assuming drive cache: write through

blkid
/dev/sdb2: UUID="..." TYPE="ext4" PARTLABEL="Linux filesystem" PARTUUID="..."
[rootfs ]#

This leads me to believe that somehow the process of recognizing the USB key and getting it into a usable state is too slow. Consequently, it is not available when systemd tries to mount / and thus aborts the whole process. Has anyone experienced a similar behavior before and possibly found a solution? Is it perhaps possible to insert a pause during systemd startup?

What I did discover is that sometimes (perhaps once out of ten tries) I can successfully boot from the USB key when I select Arch fallback, but this is fairly inconsistent and certainly not a long-term solution.

Any pointers you might have are highly appreciated. Thanks in advance for trying to help me.

Cheers,

Smoerrebroed

Last edited by Smoerrebroed (2017-05-14 15:50:57)

Trilby

Inspector Parrot

Registered: 2011-11-29

Posts: 30,333

Website

Re: [SOLVED] Arch/GRUB/GPT on USB 3.0 Stick

Is that the verbatim output, or did you siimplify/remove parts - if so please be clear about what revisions you made to the error output.

---

"UNIX is simple and coherent" - Dennis Ritchie; "GNU's Not Unix" - Richard Stallman

tom.ty89

Member

Registered: 2012-11-15

Posts: 897

Re: [SOLVED] Arch/GRUB/GPT on USB 3.0 Stick

Make sure you don't exclude the udev hook since the init will only poll/wait the requested device  (root= / cryptdevice=) for 10 seconds (well the default), then make sure the necessary drivers are included in the initramfs image (if unsure try/use the fallback image), then make sure the UUID in the grub entry (again, root= / cryptdevice=) set is correct.

Did the init wait for 10 seconds before it spitted "device not found"? Also is sdb(2) the usb disk(root partition)?

In that's the case try adding rootdelay=15 (or something even higher) to the grub entry.

P.S. Your stick probably sucks, better not use it for a system installation.

Smoerrebroed

Member

From: Germany

Registered: 2011-07-24

Posts: 110

Re: [SOLVED] Arch/GRUB/GPT on USB 3.0 Stick

Is that the verbatim output, or did you siimplify/remove parts

It's exactly what is presented on screen, except for the UUID which I omitted for brevity. (However, it is the correct UUID.)

Make sure you don't exclude the udev hook

I made sure - it's in there by default. I only moved the block hook in the position right next to udev (according to the Arch Wiki).

make sure the necessary drivers are included in the initramfs image

All required drivers are included. UUID matches as per above.

In that's the case try adding rootdelay=15 (or something even higher) to the grub entry.

That did the trick! I found that I can go as low as rootdelay=12. Anything below that and booting fails. Many thanks for your help.

P.S. Your stick probably sucks, better not use it for a system installation.

Well, so far I am rather pleased with its performance, and I figured I'd use a rather fast USB stick for this setup. I know it's not ideal, but at the moment it's the only solution I can implement. Thanks again!

Cheers,

Smoerrebroed