[SOLVED]sysctl: cannot stat /proc/sys/root: No such file or directory

likemike · 2020-01-12 03:51:19

I'm following https://wiki.archlinux.org/index.php/LV … lume_types to set up raid0 with lvm and it says: If the root file system resides in a logical volume, the root= kernel parameter must be pointed to the mapped device, e.g /dev/vg-name/lv-name.

My root filesystem exists in a logical volume and I attempted to point this kernel parameter to my mapped device with:

sysctl -w root=/dev/VolGroup0/lvmraidoot

It returns the error:

sysctl: cannot stat /proc/sys/root: No such file or directory

I've read some stuff on the wiki regarding grub and set root= but I'm not sure if this is the same thing I'm looking for.
What am I missing here when I enter the command? I feel as if it is something obvious although I'm not sure.

Any insight is greatly appreciated

-likemike

Last edited by likemike (2020-01-12 06:43:55)

jasonwryan · 2020-01-12 03:58:30

Why are you using sysctl? What are you actually trying to do?

likemike · 2020-01-12 04:06:05

jasonwryan wrote:

Why are you using sysctl? What are you actually trying to do?

I'm trying to set up LVM raid0 and install arch on it by following what the LVM wiki says about "If the root file system resides in a logical volume, the root= kernel parameter must be pointed to the mapped device, e.g /dev/vg-name/lv-name."
because my root file system resides on a logical volume. So I'm tryring to point the root= kernel parameter to my root logical volume. I read somewhere that you can add kernel parameters at runtime using sysctl -w command. Is this not the way to go about doing this?

Last edited by likemike (2020-01-12 04:07:52)

jasonwryan · 2020-01-12 04:39:47

The instructions are for configuring your boot loader/manager. You aren't trying to do this at runtime. The "root=" parameter is added to your grub/syslinux/systemd-boot config.

likemike · 2020-01-12 05:34:51

jasonwryan wrote:

The instructions are for configuring your boot loader/manager. You aren't trying to do this at runtime. The "root=" parameter is added to your grub/syslinux/systemd-boot config.

There doesn't seem to be a /grub/syslinux/ directory or systemd-boot file within it

If this is something that is added after grub-install I can't get to it because grub-install --target=i386-pc returns

grub-install: error: disk 'lvmid/...' not found

I have added lvm to the GRUB_PRELOAD_MODULES

Last edited by likemike (2020-01-12 05:38:18)

jasonwryan · 2020-01-12 06:12:00

That is a separate issue: you are now trying to configure your boot loader, this has nothing to do with sysctl.

Mark this solved, and open a new thread with exact details of what you have done, commands and output, and your grub config.

likemike · 2020-01-12 06:57:53

jasonwryan wrote:

That is a separate issue: you are now trying to configure your boot loader, this has nothing to do with sysctl.
Mark this solved, and open a new thread with exact details of what you have done, commands and output, and your grub config.

I read on: https://bbs.archlinux.org/viewtopic.php?id=203645 that grub doesn't install on lvm with raid so although there probably is a way to do it I settled for setting up a regular lvm install. Grub installed fine on that and everything is working so making a new post isn't needed. Thanks for clearing up the root= thing though.

Arch Linux

#1 2020-01-12 03:51:19

[SOLVED]sysctl: cannot stat /proc/sys/root: No such file or directory

#2 2020-01-12 03:58:30

Re: [SOLVED]sysctl: cannot stat /proc/sys/root: No such file or directory

#3 2020-01-12 04:06:05

Re: [SOLVED]sysctl: cannot stat /proc/sys/root: No such file or directory

#4 2020-01-12 04:39:47

Re: [SOLVED]sysctl: cannot stat /proc/sys/root: No such file or directory

#5 2020-01-12 05:34:51

Re: [SOLVED]sysctl: cannot stat /proc/sys/root: No such file or directory

#6 2020-01-12 06:12:00

Re: [SOLVED]sysctl: cannot stat /proc/sys/root: No such file or directory

#7 2020-01-12 06:57:53

Re: [SOLVED]sysctl: cannot stat /proc/sys/root: No such file or directory

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