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grub2 boot MBR and raid error [solved]
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Frautoincnam
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Joined: 19 May 2017
Posts: 330

PostPosted: Thu Dec 19, 2024 8:36 pm    Post subject: grub2 boot MBR and raid error [solved] Reply with quote

[solution below]

Hi,

I am seeking your help because I can't figure this out on my own.

I have a computer running Gentoo for many years, working perfectly, with a software RAID 1 setup. It has six partitions on each disk (MBR), each configured as a RAID array.
The first partition on each disk is a boot partition, in ext2, and the rest are in ext4.

Code:
/etc/mdadm.conf:
DEVICE /dev/sd[ab][123567]
ARRAY /dev/md123 metadata=0.90 UUID=f3a1266a:b8a3d1c0:58f2f8e7:254eabdb
ARRAY /dev/md122 metadata=0.90 UUID=b98a2770:1b208d6e:58f2f8e7:254eabdb
ARRAY /dev/md125 metadata=0.90 UUID=526e6df9:9f1fd15b:58f2f8e7:254eabdb
ARRAY /dev/md124 metadata=0.90 UUID=0627d9a2:9b8f1319:58f2f8e7:254eabdb
ARRAY /dev/md126 metadata=0.90 UUID=60e93244:ca06e195:58f2f8e7:254eabdb
ARRAY /dev/md127 metadata=0.90 UUID=87af9f2a:1ad04950:58f2f8e7:254eabdb

Code:
/etc/fstab:
/dev/md123              /boot           ext2            noauto,noatime          1 2
/dev/md122              /               ext4            noatime,acl,user_xattr  0 1
/dev/md125              none            swap            sw                      0 0
/dev/md124              /tmp            ext4            nodev,noexec            1 2
/dev/md126             /home           ext4            noatime,acl,usrquota    1 2
/dev/md127              /var            ext4            noatime,acl,user_xattr  1 2

Code:
/boot/grub/grub.cfg:
#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
if [ -s $prefix/grubenv ]; then
  load_env
fi
if [ "${next_entry}" ] ; then
   set default="${next_entry}"
   set next_entry=
   save_env next_entry
   set boot_once=true
else
   set default="0"
fi

if [ x"${feature_menuentry_id}" = xy ]; then
  menuentry_id_option="--id"
else
  menuentry_id_option=""
fi

export menuentry_id_option

if [ "${prev_saved_entry}" ]; then
  set saved_entry="${prev_saved_entry}"
  save_env saved_entry
  set prev_saved_entry=
  save_env prev_saved_entry
  set boot_once=true
fi

function savedefault {
  if [ -z "${boot_once}" ]; then
    saved_entry="${chosen}"
    save_env saved_entry
  fi
}

function load_video {
  if [ x$feature_all_video_module = xy ]; then
    insmod all_video
  else
    insmod efi_gop
    insmod efi_uga
    insmod ieee1275_fb
    insmod vbe
    insmod vga
    insmod video_bochs
    insmod video_cirrus
  fi
}

if [ x$feature_default_font_path = xy ] ; then
   font=unicode
else
insmod part_msdos
insmod part_msdos
insmod diskfilter
insmod mdraid09
insmod ext2
set root='mduuid/b98a27701b208d6e58f2f8e7254eabdb'
if [ x$feature_platform_search_hint = xy ]; then
  search --no-floppy --fs-uuid --set=root --hint='mduuid/b98a27701b208d6e58f2f8e7254eabdb'  4242e078-8721-49cc-b7c4-78ad222b0e13
else
  search --no-floppy --fs-uuid --set=root 4242e078-8721-49cc-b7c4-78ad222b0e13
fi
    font="/usr/share/grub/unicode.pf2"
fi

if loadfont $font ; then
  set gfxmode=1600x1200x32
  load_video
  insmod gfxterm
  set locale_dir=$prefix/locale
  set lang=fr_FR
  insmod gettext
fi
terminal_output gfxterm
if [ x$feature_timeout_style = xy ] ; then
  set timeout_style=menu
  set timeout=5
# Fallback normal timeout code in case the timeout_style feature is
# unavailable.
else
  set timeout=5
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/10_linux ###
menuentry 'Gentoo GNU/Linux' --class gentoo --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-4242e078-8721-49cc-b7c4-78ad222b0e13' {
        load_video
        set gfxpayload=keep
        insmod gzio
        insmod part_msdos
        insmod part_msdos
        insmod diskfilter
        insmod mdraid09
        insmod ext2
        set root='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'
        if [ x$feature_platform_search_hint = xy ]; then
          search --no-floppy --fs-uuid --set=root --hint='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'  e3150191-4514-4f87-82cb-58101767a269
        else
          search --no-floppy --fs-uuid --set=root e3150191-4514-4f87-82cb-58101767a269
        fi
        echo    'Chargement de Linux 6.6.62-gentoo…'
        linux   /vmlinuz-6.6.62-gentoo root=/dev/md122 ro  irqpoll fbcon=nodefer
}
submenu 'Options avancées pour Gentoo GNU/Linux' $menuentry_id_option 'gnulinux-advanced-4242e078-8721-49cc-b7c4-78ad222b0e13' {
        menuentry 'Gentoo GNU/Linux, avec Linux 6.6.62-gentoo' --class gentoo --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.6.62-gentoo-advanced-4242e078-8721-49cc-b7c4-78ad222b0e13' {
                load_video
                set gfxpayload=keep
                insmod gzio
                insmod part_msdos
                insmod part_msdos
                insmod diskfilter
                insmod mdraid09
                insmod ext2
                set root='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'
                if [ x$feature_platform_search_hint = xy ]; then
                  search --no-floppy --fs-uuid --set=root --hint='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'  e3150191-4514-4f87-82cb-58101767a269
                else
                  search --no-floppy --fs-uuid --set=root e3150191-4514-4f87-82cb-58101767a269
                fi
                echo    'Chargement de Linux 6.6.62-gentoo…'
                linux   /vmlinuz-6.6.62-gentoo root=/dev/md122 ro  irqpoll fbcon=nodefer
        }
        menuentry 'Gentoo GNU/Linux, avec Linux 6.6.62-gentoo (mode de dépannage)' --class gentoo --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.6.62-gentoo-recovery-4242e078-8721-49cc-b7c4-78ad222b0e13' {
                load_video
                set gfxpayload=keep
                insmod gzio
                insmod part_msdos
                insmod part_msdos
                insmod diskfilter
                insmod mdraid09
                insmod ext2
                set root='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'
                if [ x$feature_platform_search_hint = xy ]; then
                  search --no-floppy --fs-uuid --set=root --hint='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'  e3150191-4514-4f87-82cb-58101767a269
                else
                  search --no-floppy --fs-uuid --set=root e3150191-4514-4f87-82cb-58101767a269
                fi
                echo    'Chargement de Linux 6.6.62-gentoo…'
                linux   /vmlinuz-6.6.62-gentoo root=/dev/md122 ro single
        }
}

### END /etc/grub.d/10_linux ###

### BEGIN /etc/grub.d/20_linux_xen ###
### END /etc/grub.d/20_linux_xen ###

### BEGIN /etc/grub.d/25_bli ###
if [ "$grub_platform" = "efi" ]; then
  insmod bli
fi
### END /etc/grub.d/25_bli ###

### BEGIN /etc/grub.d/30_os-prober ###
### END /etc/grub.d/30_os-prober ###

### BEGIN /etc/grub.d/30_uefi-firmware ###
if [ "$grub_platform" = "efi" ]; then
        menuentry 'UEFI Firmware Settings' $menuentry_id_option 'uefi-firmware' {
                fwsetup
        }
fi
### END /etc/grub.d/30_uefi-firmware ###

### BEGIN /etc/grub.d/39_memtest86+ ###
submenu 'Memtest86+' {
        if [ "x$grub_platform" = xpc ]; then
        menuentry 'Memtest86+ 64bit' {
                insmod part_msdos
                insmod part_msdos
                insmod diskfilter
                insmod mdraid09
                insmod ext2
                set root='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'
                if [ x$feature_platform_search_hint = xy ]; then
                  search --no-floppy --fs-uuid --set=root --hint='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'  e3150191-4514-4f87-82cb-58101767a269
                else
                  search --no-floppy --fs-uuid --set=root e3150191-4514-4f87-82cb-58101767a269
                fi
                linux "/memtest86plus/memtest64.bios"
        }
        fi
        if [ "x$grub_platform" = xefi ]; then
        menuentry 'Memtest86+ 64bit UEFI' {
                insmod part_msdos
                insmod part_msdos
                insmod diskfilter
                insmod mdraid09
                insmod ext2
                set root='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'
                if [ x$feature_platform_search_hint = xy ]; then
                  search --no-floppy --fs-uuid --set=root --hint='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'  e3150191-4514-4f87-82cb-58101767a269
                else
                  search --no-floppy --fs-uuid --set=root e3150191-4514-4f87-82cb-58101767a269
                fi
                chainloader "/memtest86plus/memtest.efi64"
        }
        fi
}
### END /etc/grub.d/39_memtest86+ ###

### BEGIN /etc/grub.d/40_custom ###
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
### END /etc/grub.d/40_custom ###

### BEGIN /etc/grub.d/41_custom ###
if [ -f  ${config_directory}/custom.cfg ]; then
  source ${config_directory}/custom.cfg
elif [ -z "${config_directory}" -a -f  $prefix/custom.cfg ]; then
  source $prefix/custom.cfg
fi
### END /etc/grub.d/41_custom ###


Everything was working perfectly.
However, as the usage of this computer has completely changed, I wanted to reconsider the partitioning. I aimed to have only a single partition, including boot, without separate /var, /home, and /tmp, and no swap.
So, I booted into the Gentoo live CD (in Legacy BIOS mode) and played with the partitions until I ended up breaking everything.
But that's not a problem since I obviously have backups of everything.
I then:

    - deleted everything
    - created a single partition per disk (/dev/sda1 and /dev/sdb1)
    - assembled them in RAID
    - formatted /dev/md127 in ext4
    - mounted it on /mnt/gentoo
    - fully restored my backup
    - chrooted into /dev/md127
    - reinstalled GRUB on both disks
    - regenerated the grub.cfg
    - updated mdadm.conf and fstab
    - exited the chroot, unmounted everything, and rebooted

And then, it was impossible to boot, with the infamous message:
Code:
/dev/root: Can't open blockdev
VFS: Cannont open root device "/dev/md127" or unknown-block(0,0): error -6
Please append a coorect "root=" boot option; here are the available partitions:
0800 117220824 sda
 driver : sd
  0801 117219800 sda1 0fed8d8f-01
0810 117220824 sdb
 driver : sd
  0811 117219800 sda1 0fed8d8f-01
0b00 1048575 sr0
 driver: sr
List of all bdev filesystems:
ext3
ext4
ext2
vfat
msdos
iso9660
udf

Since then, I have tried many things, all without success.
- I thought it might be due to the RAID version. I redid everything with version 0.90, still no success.
- I thought it might be the ext4 partition (even though on another PC, I can boot from an ext4 partition on MBR without any problem, but it's not in RAID). So I redid everything with a boot partition in ext2, like I had before, but still no success.

Note that:

- I do not use an initrd; I never have, and I do not want to. It has always worked this way, and there’s no reason it should change.
- My system has been fully backed up, so the kernel, GRUB, RAID, and everything else has the same configuration as before.
- GRUB2 does detect my partitions: (hd0) (hd0,msdos2) (hd0,msdos1) (hd1) (hd1,msdos2) (hd1,msdos1) (md/md127) (md/md126)
- I was able to boot from /dev/sda1 (when I had only one ext4 partition), but that's not my goal.
- Apart from the UUIDs and the name of /dev/md changing, I don't see any differences between the two GRUB setups:
Code:
@@ -63,11 +63,11 @@
 insmod diskfilter
 insmod mdraid09
 insmod ext2
-set root='mduuid/b98a27701b208d6e58f2f8e7254eabdb'
+set root='mduuid/6e88fa375f36404acb201669f728008a'
 if [ x$feature_platform_search_hint = xy ]; then
-  search --no-floppy --fs-uuid --set=root --hint='mduuid/b98a27701b208d6e58f2f8e7254eabdb'  4242e078-8721-49cc-b7c4-78ad222b0e13
+  search --no-floppy --fs-uuid --set=root --hint='mduuid/6e88fa375f36404acb201669f728008a'  c136d2da-2704-46d1-ae3b-b528d7b87212
 else
-  search --no-floppy --fs-uuid --set=root 4242e078-8721-49cc-b7c4-78ad222b0e13
+  search --no-floppy --fs-uuid --set=root c136d2da-2704-46d1-ae3b-b528d7b87212
 fi
     font="/usr/share/grub/unicode.pf2"
 fi
@@ -89,10 +89,11 @@
 else
   set timeout=5
 fi
+play 60 800 1
 ### END /etc/grub.d/00_header ###
 
 ### BEGIN /etc/grub.d/10_linux ###
-menuentry 'Gentoo GNU/Linux' --class gentoo --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-4242e078-8721-49cc-b7c4-78ad222b0e13' {
+menuentry 'Gentoo GNU/Linux' --class gentoo --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-c136d2da-2704-46d1-ae3b-b528d7b87212' {
        load_video
        set gfxpayload=keep
        insmod gzio
@@ -101,17 +102,17 @@
        insmod diskfilter
        insmod mdraid09
        insmod ext2
-       set root='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'
+       set root='mduuid/ff816f4d8b3d8692cb201669f728008a'
        if [ x$feature_platform_search_hint = xy ]; then
-         search --no-floppy --fs-uuid --set=root --hint='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'  e3150191-4514-4f87-82cb-58101767a269
+         search --no-floppy --fs-uuid --set=root --hint='mduuid/ff816f4d8b3d8692cb201669f728008a'  b12427c1-b289-462e-9e9c-6723c9e01425
        else
-         search --no-floppy --fs-uuid --set=root e3150191-4514-4f87-82cb-58101767a269
+         search --no-floppy --fs-uuid --set=root b12427c1-b289-462e-9e9c-6723c9e01425
        fi
        echo    'Chargement de Linux 6.6.62-gentoo…'
-       linux   /vmlinuz-6.6.62-gentoo root=/dev/md122 ro  irqpoll fbcon=nodefer
+       linux   /vmlinuz-6.6.62-gentoo root=/dev/md126 ro  irqpoll fbcon=nodefer
 }
-submenu 'Options avancées pour Gentoo GNU/Linux' $menuentry_id_option 'gnulinux-advanced-4242e078-8721-49cc-b7c4-78ad222b0e13' {
-       menuentry 'Gentoo GNU/Linux, avec Linux 6.6.62-gentoo' --class gentoo --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.6.62-gentoo-advanced-4242e078-8721-49cc-b7c4-78ad222b0e13' {
+submenu 'Options avancées pour Gentoo GNU/Linux' $menuentry_id_option 'gnulinux-advanced-c136d2da-2704-46d1-ae3b-b528d7b87212' {
+       menuentry 'Gentoo GNU/Linux, avec Linux 6.6.62-gentoo' --class gentoo --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.6.62-gentoo-advanced-c136d2da-2704-46d1-ae3b-b528d7b87212' {
                load_video
                set gfxpayload=keep
                insmod gzio
@@ -120,16 +121,16 @@
                insmod diskfilter
                insmod mdraid09
                insmod ext2
-               set root='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'
+               set root='mduuid/ff816f4d8b3d8692cb201669f728008a'
                if [ x$feature_platform_search_hint = xy ]; then
-                 search --no-floppy --fs-uuid --set=root --hint='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'  e3150191-4514-4f87-82cb-58101767a269
+                 search --no-floppy --fs-uuid --set=root --hint='mduuid/ff816f4d8b3d8692cb201669f728008a'  b12427c1-b289-462e-9e9c-6723c9e01425
                else
-                 search --no-floppy --fs-uuid --set=root e3150191-4514-4f87-82cb-58101767a269
+                 search --no-floppy --fs-uuid --set=root b12427c1-b289-462e-9e9c-6723c9e01425
                fi
                echo    'Chargement de Linux 6.6.62-gentoo…'
-               linux   /vmlinuz-6.6.62-gentoo root=/dev/md122 ro  irqpoll fbcon=nodefer
+               linux   /vmlinuz-6.6.62-gentoo root=/dev/md126 ro  irqpoll fbcon=nodefer
        }
-       menuentry 'Gentoo GNU/Linux, avec Linux 6.6.62-gentoo (mode de dépannage)' --class gentoo --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.6.62-gentoo-recovery-4242e078-8721-49cc-b7c4-78ad222b0e13' {
+       menuentry 'Gentoo GNU/Linux, avec Linux 6.6.62-gentoo (mode de dépannage)' --class gentoo --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.6.62-gentoo-recovery-c136d2da-2704-46d1-ae3b-b528d7b87212' {
                load_video
                set gfxpayload=keep
                insmod gzio
@@ -138,14 +139,14 @@
                insmod diskfilter
                insmod mdraid09
                insmod ext2
-               set root='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'
+               set root='mduuid/ff816f4d8b3d8692cb201669f728008a'
                if [ x$feature_platform_search_hint = xy ]; then
-                 search --no-floppy --fs-uuid --set=root --hint='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'  e3150191-4514-4f87-82cb-58101767a269
+                 search --no-floppy --fs-uuid --set=root --hint='mduuid/ff816f4d8b3d8692cb201669f728008a'  b12427c1-b289-462e-9e9c-6723c9e01425
                else
-                 search --no-floppy --fs-uuid --set=root e3150191-4514-4f87-82cb-58101767a269
+                 search --no-floppy --fs-uuid --set=root b12427c1-b289-462e-9e9c-6723c9e01425
                fi
                echo    'Chargement de Linux 6.6.62-gentoo…'
-               linux   /vmlinuz-6.6.62-gentoo root=/dev/md122 ro single
+               linux   /vmlinuz-6.6.62-gentoo root=/dev/md126 ro single
        }
 }
 
@@ -180,11 +181,11 @@
                insmod diskfilter
                insmod mdraid09
                insmod ext2
-               set root='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'
+               set root='mduuid/ff816f4d8b3d8692cb201669f728008a'
                if [ x$feature_platform_search_hint = xy ]; then
-                 search --no-floppy --fs-uuid --set=root --hint='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'  e3150191-4514-4f87-82cb-58101767a269
+                 search --no-floppy --fs-uuid --set=root --hint='mduuid/ff816f4d8b3d8692cb201669f728008a'  b12427c1-b289-462e-9e9c-6723c9e01425
                else
-                 search --no-floppy --fs-uuid --set=root e3150191-4514-4f87-82cb-58101767a269
+                 search --no-floppy --fs-uuid --set=root b12427c1-b289-462e-9e9c-6723c9e01425
                fi
                linux "/memtest86plus/memtest64.bios"
        }
@@ -196,11 +197,11 @@
                insmod diskfilter
                insmod mdraid09
                insmod ext2
-               set root='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'
+               set root='mduuid/ff816f4d8b3d8692cb201669f728008a'
                if [ x$feature_platform_search_hint = xy ]; then
-                 search --no-floppy --fs-uuid --set=root --hint='mduuid/f3a1266ab8a3d1c058f2f8e7254eabdb'  e3150191-4514-4f87-82cb-58101767a269
+                 search --no-floppy --fs-uuid --set=root --hint='mduuid/ff816f4d8b3d8692cb201669f728008a'  b12427c1-b289-462e-9e9c-6723c9e01425
                else
-                 search --no-floppy --fs-uuid --set=root e3150191-4514-4f87-82cb-58101767a269
+                 search --no-floppy --fs-uuid --set=root b12427c1-b289-462e-9e9c-6723c9e01425
                fi
                chainloader "/memtest86plus/memtest.efi64"
        }

- I tried to better adjust the kernel, but still without success:
Code:
@@ -7,9 +7,9 @@
 CONFIG_GCC_VERSION=140201
 CONFIG_CLANG_VERSION=0
 CONFIG_AS_IS_GNU=y
-CONFIG_AS_VERSION=24200
+CONFIG_AS_VERSION=24301
 CONFIG_LD_IS_BFD=y
-CONFIG_LD_VERSION=24200
+CONFIG_LD_VERSION=24301
 CONFIG_LLD_VERSION=0
 CONFIG_CC_CAN_LINK=y
 CONFIG_CC_CAN_LINK_STATIC=y
@@ -1671,9 +1671,9 @@
 CONFIG_MD=y
 CONFIG_BLK_DEV_MD=y
 CONFIG_MD_AUTODETECT=y
-CONFIG_MD_BITMAP_FILE=y
+# CONFIG_MD_BITMAP_FILE is not set
 # CONFIG_MD_LINEAR is not set
-CONFIG_MD_RAID0=y
+# CONFIG_MD_RAID0 is not set
 CONFIG_MD_RAID1=y
 # CONFIG_MD_RAID10 is not set
 # CONFIG_MD_RAID456 is not set
@@ -1692,10 +1692,9 @@
 # CONFIG_DM_EBS is not set
 # CONFIG_DM_ERA is not set
 # CONFIG_DM_CLONE is not set
-CONFIG_DM_MIRROR=y
-# CONFIG_DM_LOG_USERSPACE is not set
+# CONFIG_DM_MIRROR is not set
 # CONFIG_DM_RAID is not set
-CONFIG_DM_ZERO=y
+# CONFIG_DM_ZERO is not set
 # CONFIG_DM_MULTIPATH is not set
 # CONFIG_DM_DELAY is not set
 # CONFIG_DM_DUST is not set

Not understanding where the problem comes from, I obviously don't know how to fix it.

I hope I haven't forgotten anything and am counting on your help...
Thanks in advance.


Last edited by Frautoincnam on Fri Dec 20, 2024 2:42 am; edited 1 time in total
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pingtoo
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PostPosted: Thu Dec 19, 2024 8:59 pm    Post subject: Reply with quote

Code:
/dev/root: Can't open blockdev
VFS: Cannont open root device "/dev/md127" or unknown-block(0,0): error -6


Are you sure you should use "/dev/md127" for root?

Your grub.cfg does not have anywhere reference to "/dev/md127", so are you share the one use for boot?
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Frautoincnam
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PostPosted: Thu Dec 19, 2024 9:23 pm    Post subject: Reply with quote

pingtoo wrote:
Code:
/dev/root: Can't open blockdev
VFS: Cannont open root device "/dev/md127" or unknown-block(0,0): error -6


Are you sure you should use "/dev/md127" for root?


This message was when I tried with only one part ext4.
Quote:
Your grub.cfg does not have anywhere reference to "/dev/md127", so are you share the one use for boot?

now, it's /dev/md126, according to:
Code:
(chroot) 15:49:24 root@livecd / # blkid
/dev/md127: UUID="b12427c1-b289-462e-9e9c-6723c9e01425" BLOCK_SIZE="1024" TYPE="ext2"
/dev/sdb2: UUID="6e88fa37-5f36-404a-cb20-1669f728008a" TYPE="linux_raid_member" PARTUUID="01550dc4-02"
/dev/sdb1: UUID="ff816f4d-8b3d-8692-cb20-1669f728008a" TYPE="linux_raid_member" PARTUUID="01550dc4-01"
/dev/loop0: BLOCK_SIZE="131072" TYPE="squashfs"
/dev/sdc2: SEC_TYPE="msdos" LABEL_FATBOOT="GENTOOLIVE" LABEL="GENTOOLIVE" UUID="0936-65AE" BLOCK_SIZE="512" TYPE="vfat" PARTUUID="6b8b4567-02"
/dev/sdc1: BLOCK_SIZE="2048" UUID="2020-10-01-13-58-43-59" LABEL="Gentoo amd64 20201001T120249Z" TYPE="iso9660" PTUUID="6b8b4567" PTTYPE="dos" PARTUUID="6b8b4567-01"
/dev/md126: UUID="c136d2da-2704-46d1-ae3b-b528d7b87212" BLOCK_SIZE="4096" TYPE="ext4"
/dev/sda2: UUID="6e88fa37-5f36-404a-cb20-1669f728008a" TYPE="linux_raid_member" PARTUUID="01550dc4-02"
/dev/sda1: UUID="ff816f4d-8b3d-8692-cb20-1669f728008a" TYPE="linux_raid_member" PARTUUID="01550dc4-01"

Code:
/dev/md127              /boot           ext             noauto,noatime          1 2
/dev/md126              /               ext4            noatime,acl,user_xattr  0 1

Code:
DEVICE /dev/sd[ab][1]
ARRAY /dev/md127 metadata=0.90 UUID=ff816f4d:8b3d8692:cb201669:f728008a
ARRAY /dev/md126 metadata=0.90 UUID=6e88fa37:5f36404a:cb201669:f728008a

I don't create grub.cfg manualy. I use grub-mkconfig -o /boot/grub/grub.cfg as I always used.
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pingtoo
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PostPosted: Thu Dec 19, 2024 9:35 pm    Post subject: Reply with quote

May be you can try to use PARTUUID for root?

use
Code:
lsblk -o '+PARTUUID'
to get md126's PARTUUID and write it down,

Then boot into grub and press 'e' for the entry you want to boot. Modify the root=. from root=/dev/md126 to root=PARTUUID=<whatever you got from the lsblk output> Then try to boot from there to see if linux kernel can pick up the correct device for rootfs.

If that work we just need to fix grub.cfg and try to figure it out how to make grub use PARTUUID.
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Frautoincnam
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PostPosted: Thu Dec 19, 2024 9:41 pm    Post subject: Reply with quote

I doubt that this will work, I've already tried so many things. And even if it did, it wouldn't explain at all why I would now have to put PARTUUIDs when I've always done without them.
What, in the detailed configurations I've given, would justify the operation suddenly changing just because I redid the partitioning?
And md seems not to have PARTUUID:
Code:
livecd ~ # lsblk -o '+PARTUUID'
NAME      MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT  PARTUUID
loop0       7:0    0 388.1M  1 loop  /mnt/livecd
sda         8:0    0 111.8G  0 disk             
├─sda1      8:1    0   100M  0 part              01550dc4-01
│ └─md127   9:127  0   100M  0 raid1             
└─sda2      8:2    0 111.7G  0 part              01550dc4-02
  └─md126   9:126  0 111.7G  0 raid1             
sdb         8:16   0 111.8G  0 disk             
├─sdb1      8:17   0   100M  0 part              01550dc4-01
│ └─md127   9:127  0   100M  0 raid1             
└─sdb2      8:18   0 111.7G  0 part              01550dc4-02
  └─md126   9:126  0 111.7G  0 raid1             
sdc         8:32   1   496M  0 disk             
├─sdc1      8:33   1   425M  0 part  /mnt/cdrom  6b8b4567-01
└─sdc2      8:34   1   6.4M  0 part              6b8b4567-02

I'll wait for other suggestions.
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PostPosted: Thu Dec 19, 2024 10:18 pm    Post subject: Reply with quote

Frautoincnam,

Raid sets do not have a PARTUUID as they are not partitions.
Using filesystem UUID requires an initrd.

You must use kernel raid set auto assembly to avoid an initrd.
That only works with raid metadata version 0.90
Its also been on the kernel feature removal list for a long time.

Please post the complete output from
mdadm -E /dev/<partition_donated_to_root>
That will tell us how your raid set is defined.

Use wgetpaste to share your kernel .config file too please.
You may need to try several services to find one that will accept such a large file.
Tell us the link.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
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Frautoincnam
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PostPosted: Thu Dec 19, 2024 10:33 pm    Post subject: Reply with quote

NeddySeagoon wrote:
Frautoincnam,

Hi, and thanks for your help.
Quote:
Raid sets do not have a PARTUUID as they are not partitions.

Yes. It was just an answer.
Quote:
Using filesys*em UUID requires an initrd.

Ok.
Quote:
You must use kernel raid set auto assembly to avoid an initrd.

I have all of this since it has always worked so far.
Quote:
That only works with raid metadata version 0.90

I understood that.
Quote:
Its also been on the kernel feature removal list for a long time.

Oh...
Quote:
Please post the complete output from
mdadm -E /dev/<partition_donated_to_root>

Code:
livecd ~ # cat /proc/mdstat
Personalities : [raid1]
md126 : active raid1 sdb2[1] sda2[0]
      117117312 blocks [2/2] [UU]
      bitmap: 0/1 pages [0KB], 65536KB chunk

md127 : active raid1 sdb1[1] sda1[0]
      102336 blocks [2/2] [UU]
     
unused devices: <none>
livecd ~ # mdadm -E /dev/sda2
/dev/sda2:
          Magic : a92b4efc
        Version : 0.90.00
           UUID : 6e88fa37:5f36404a:cb201669:f728008a (local to host livecd)
  Creation Time : Thu Dec 19 18:27:40 2024
     Raid Level : raid1
  Used Dev Size : 117117312 (111.69 GiB 119.93 GB)
     Array Size : 117117312 (111.69 GiB 119.93 GB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 126

    Update Time : Thu Dec 19 22:17:08 2024
          State : clean
Internal Bitmap : present
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0
       Checksum : ef6b608 - correct
         Events : 120


      Number   Major   Minor   RaidDevice State
this     0       8        2        0      active sync   /dev/sda2

   0     0       8        2        0      active sync   /dev/sda2
   1     1       8       18        1      active sync   /dev/sdb2
livecd ~ # mdadm -E /dev/sdb2
/dev/sdb2:
          Magic : a92b4efc
        Version : 0.90.00
           UUID : 6e88fa37:5f36404a:cb201669:f728008a (local to host livecd)
  Creation Time : Thu Dec 19 18:27:40 2024
     Raid Level : raid1
  Used Dev Size : 117117312 (111.69 GiB 119.93 GB)
     Array Size : 117117312 (111.69 GiB 119.93 GB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 126

    Update Time : Thu Dec 19 22:17:08 2024
          State : clean
Internal Bitmap : present
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0
       Checksum : ef6b61a - correct
         Events : 120


      Number   Major   Minor   RaidDevice State
this     1       8       18        1      active sync   /dev/sdb2

   0     0       8        2        0      active sync   /dev/sda2
   1     1       8       18        1      active sync   /dev/sdb2

Quote:
Use wgetpaste to share your kernel .config file too please.
You may need to try several services to f|nd one that will accept such a large file.
Tell us the link.

https://paste.gentoo.zip/y1D2LkvZ
Edit : I just added CONFIG_DM_RAID with no success.


Last edited by Frautoincnam on Thu Dec 19, 2024 11:24 pm; edited 1 time in total
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PostPosted: Thu Dec 19, 2024 10:55 pm    Post subject: Reply with quote

Quote:
Raid sets do not have a PARTUUID as they are not partitions.
Didn't know that. Learn something new everyday.

I wonder if MD does not have something that can be identified by kernel. how would kernel know which to use.

I see the LIVECD was used to show. but I remember in past post, LIVECD and actually successful booted system usually show different MD number. Is there some kind of rule to correlate them? for example md126 will acutally be md6 (as an example)
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Frautoincnam
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PostPosted: Fri Dec 20, 2024 2:41 am    Post subject: Reply with quote

[solution]

Logic dictated that there was absolutely nothing to change in terms of configuration, kernel, grub, etc. since nothing had changed between the functional state and the current state. It could only be the creation of the raid, and in particular the absurd error of not having given a type to my partitions. I only had to
Code:
parted /dev/sda set 1 raid on
parted /dev/sda set 2 raid on
parted /dev/sdb set 1 raid on
parted /dev/sdb set 2 raid on

for the boot to be done without any difficulty.
I am ashamed, but I learned a lot ;)

I destroyed everything again, to rebuild as I initially wanted without a boot partition, and it obviously works.

Thank you for your attention.
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