SliTaz Forum

llev

Member

Registered: 2011-12-09

Posts: 568

root= option

Hi,

I did a harddisk install of rolling to a USB disk. It works fine, but I have to put the root partition device in the "kernel" GRUB line like so: kernel /boot/vmlinuz... root=/dev/sda2.

The problem is, I've read that the device node is not supposed to be reliable. It may well be sdb2, sdc2, etc. when I boot from this disk on another machine. So I'm looking for a stable way of specifying the root partition. Is it possible?

I've tried both root=(UUID) and root=/dev/disk/by-uuid/(UUID), to no avail. Maybe do I need to recompile the kernel with some option activated?

Thanks.

lexeii

Administrator

Registered: 2012-03-21

Posts: 1,853

Re: root= option

Hi llev,

I not tried full USB installation for long time ago. Can you try something like that?

[c]title SliTaz Rolling
rootnoverify (hd0,0)
kernel (hd0,0)/boot/bzImage rw root=UUID=f6df0c5f-bf48-4dde-843c-40098cfa1a8f lang=en_US kmap=en autologin[/c]
Note only, root=UUID=something syntax.

Maybe it will work for you.

llev

Member

Registered: 2011-12-09

Posts: 568

Re: root= option

Hi Aleksej,

Thank you for your answer. Alas this doesn't work. (Is it necessary to use rootnoverify in grub? I put only root (hd...))

When the kernel panics, it tells me: "Please append a correct root option. Here are the available partitions:" and it lists them all. Maybe is there a way to have the kernel /ask/ for the correct partition?

llev

Member

Registered: 2011-12-09

Posts: 568

Re: root= option

Based on your hint, a web search led me to look in kernel source file init/main.c, then init/do_mounts.c.

There you find that root=PARTUUID=stuff should work (CONFIG_BLOCK is set in Slitaz' kernel).

Alas it doesn't work either, and I have too few screen lines to see why.

llev

Member

Registered: 2011-12-09

Posts: 568

Re: root= option

In fact, according to this: http://archives.gentoo.org/gentoo-user/msg_35eb3187ef8be8a23cdec253b66b5a59.xml , PARTUUID is not the same as UUID, and one needs a GPT instead of an MBR to have PARTUUIDs.

mojo

Administrator

Registered: 2011-03-29

Posts: 2,174

Re: root= option

Slitaz cooking 32bit kernel compiled November 22, 2013 works with root=UUID= or root=LABEL=