[SOLVED] RHEL 6.0 boot partition disappears once booted into the OS.

localgameworld · 11-21-2011, 12:18 AM

I have a RHEL 6.0 installation that works fine. I have one issue, when I boot the system up, everything checks out ok, except for the routine fsck during boot:

I get this error

fsck.ext4: Unable to resolve 'UUID=534fb490-79bb-4049-bced-de65d88a4abf'

------------------------------------------------------------------------

Here is my /etc/fstab file:

#
# /etc/fstab
# Created by anaconda on Fri Nov 18 12:18:29 2011
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/VolGroup-lv_root / ext4 defaults 1 1
UUID=534fb490-79bb-4049-bced-de65d88a4abf /boot ext4 defaults 1 2
/dev/mapper/VolGroup-lv_swap swap swap defaults 0 0
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0

#===================================================EOF

Now if I change the line about the boot section to look like this below the fsck error goes away and the system continues to boot, but the whole boot partition goes missing once the RHEL 6.0 is loaded and up.

UUID=534fb490-79bb-4049-bced-de65d88a4abf /boot ext4 defaults 1 0

Is there something I am missing?

My boot device resides on /dev/sda1 but when I get booted, that device is gone.

Any assistance or guidance would be much appreciated.

syg00 · 11-21-2011, 02:33 AM

Making the symptom go away hardly deals with the (real) problem. Let's see the following (as root)

Code:

parted -l
ls -l /dev/disk/by-uuid/

Edit: of course, you should be asking this of Redhat support (that you are paying for) given this is RHEL ...

localgameworld · 11-21-2011, 08:28 AM

Here are the two outputs requested:

[root@localhost ~]# parted -l
Model: ATA Maxtor 6E040T0 (scsi)
Disk /dev/sda: 41.1GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
1 1049kB 525MB 524MB primary ext4 boot
2 525MB 41.1GB 40.6GB primary lvm

Model: Linux device-mapper (linear) (dm)
Disk /dev/mapper/VolGroup-lv_swap: 2114MB
Sector size (logical/physical): 512B/512B
Partition Table: loop

Number Start End Size File system Flags
1 0.00B 2114MB 2114MB linux-swap(v1)

Model: Linux device-mapper (linear) (dm)
Disk /dev/mapper/VolGroup-lv_root: 38.5GB
Sector size (logical/physical): 512B/512B
Partition Table: loop

Number Start End Size File system Flags
1 0.00B 38.5GB 38.5GB ext4

[root@localhost ~]# ls -l /dev/disk/by-uuid/
total 0
lrwxrwxrwx. 1 root root 10 Nov 21 09:23 ba6a5f0e-9fb9-41b2-a9e4-b218d940553d -> ../../dm-0
lrwxrwxrwx. 1 root root 10 Nov 21 09:23 da348bd9-4996-4d82-879c-2e69cab53dbe -> ../../dm-1

Now here is the crazy thing, I have a good backup, and on the backup the drive for the boot filesystem exists as /dev/sda1 with a symbolic link in /dev/disk/by-uuid/534fb490-79bb-4049-bced-de65d88a4abf

However, it clearly does not exist once system is booted. If I restore that data back to the system, it restores fine, I reboot...and disappears again. Strange...

syg00 · 11-21-2011, 07:20 PM

In future instead of getting creative with the colour, use [code] tags; that way the formatting gets retained. All round easier to deal with.
The device hasn't disappeared, you merely haven't asked for it to be mounted correctly. Try

Code:

mount /dev/sda1 /boot

What does

Code:

dumpe2fs /dev/sda1 | grep -i uuid

give (both commands will probably require root).

localgameworld · 11-21-2011, 11:36 PM

Code:
-------------
[QUOTE]

Quote:

[root@localhost ~]# mount /dev/sda1 /boot
mount: you must specify the filesystem type

[root@localhost ~]# mount -t ext4 /dev/sda1 /boot
mount: special device /dev/sda1 does not exist

-------------

Both failed because /dev/sda1 is no where to be found.

Code:
-------------

Quote:

[root@localhost ~]# cd /dev
[root@localhost dev]# ls -l sda*
brw-rw----. 1 root disk 8, 0 Nov 22 00:32 sda
brw-rw----. 1 root disk 8, 2 Nov 22 00:32 sda2

-------------

Here is the last command:

Code:
-------------

Quote:

[root@localhost dev]# dumpe2fs /dev/sda1 | grep -i uuid
dumpe2fs 1.41.12 (17-May-2010)
dumpe2fs: No such file or directory while trying to open /dev/sda1

-------------

I believe there is an issue with the startup procedure with /etc/rc.d/rc.sysinit
but I am not sure.

syg00 · 11-22-2011, 01:14 AM

Yeah, you're right - that is interesting.
Go get bootinfoscript. Post the RESULTS.txt so we can see what it thinks.

localgameworld · 11-23-2011, 12:57 PM

Thanks for the script. Here is the output of RESULTS.txt

Code:

[root@localhost tmp]# cat RESULTS.txt
                  Boot Info Script 0.60    from 17 May 2011


============================= Boot Info Summary: ===============================

 => Grub Legacy (v0.97) is installed in the MBR of /dev/sda and looks on the
    same drive in partition #1 for /grub/stage2 and /grub/grub.conf.

sda1: __________________________________________________________________________

    File system:       ext4
    Boot sector type:  -
    Boot sector info:
    Operating System:
    Boot files:        /grub/menu.lst /grub/grub.conf

sda2: __________________________________________________________________________

    File system:       LVM2_member
    Boot sector type:  -
    Boot sector info:

VolGroup-lv_root': _____________________________________________________________

    File system:
    Boot sector type:  Unknown
    Boot sector info:
    Mounting failed:   mount: unknown filesystem type ''

VolGroup-lv_swap': _____________________________________________________________

    File system:
    Boot sector type:  Unknown
    Boot sector info:
    Mounting failed:   mount: unknown filesystem type ''
mount: unknown filesystem type ''

============================ Drive/Partition Info: =============================

Drive: sda _____________________________________________________________________

Disk /dev/sda: 41.0 GB, 40988835840 bytes
255 heads, 63 sectors/track, 4983 cylinders, total 80056320 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes

Partition  Boot  Start Sector    End Sector  # of Sectors  Id System

/dev/sda1    *          2,048     1,026,047     1,024,000  83 Linux
/dev/sda2           1,026,048    80,056,319    79,030,272  8e Linux LVM


"blkid" output: ________________________________________________________________

Device           UUID                                   TYPE       LABEL

/dev/mapper/VolGroup-lv_root 27a98ef0-268a-4ef7-9baf-f0210bb23b31   ext4
/dev/mapper/VolGroup-lv_swap 72318e5a-1049-46b5-b255-733afee7f7f6   swap
/dev/sda1        74159698-c9b2-4027-bb8e-c7e0e62e8070   ext4
/dev/sda2        OMly0t-GyBY-jXGu-PtO9-zv2F-N2G7-H0OiFW LVM2_member

========================= "ls -R /dev/mapper/" output: =========================

/dev/mapper:
control
VolGroup-lv_root
VolGroup-lv_swap

================================ Mount points: =================================

Device           Mount_Point              Type       Options

/dev/mapper/VolGroup-lv_root /                        ext4       (rw)


============================= sda1/grub/grub.conf: =============================

--------------------------------------------------------------------------------
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE:  You have a /boot partition.  This means that
#          all kernel and initrd paths are relative to /boot/, eg.
#          root (hd0,0)
#          kernel /vmlinuz-version ro root=/dev/mapper/VolGroup-lv_root
#          initrd /initrd-[generic-]version.img
#boot=/dev/sdb
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux (2.6.32-71.el6.i686)
        root (hd0,0)
        kernel /vmlinuz-2.6.32-71.el6.i686 ro root=/dev/mapper/VolGroup-lv_root rd_LVM_LV=VolGroup/lv_root rd_LVM_LV=VolGroup/lv_swap rd_NO_LUKS rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=auto rhgb quiet
        initrd /initramfs-2.6.32-71.el6.i686.img
--------------------------------------------------------------------------------

=================== sda1: Location of files loaded by Grub: ====================

           GiB - GB             File                                 Fragment(s)

   0.258790970 = 0.277874688    grub/grub.conf                                 1
   0.258790970 = 0.277874688    grub/menu.lst                                  1
   0.258897781 = 0.277989376    grub/stage2                                    1
   0.024852753 = 0.026685440    initramfs-2.6.32-71.el6.i686.img               5
   0.031493187 = 0.033815552    vmlinuz-2.6.32-71.el6.i686                     2

======================== Unknown MBRs/Boot Sectors/etc: ========================

Unknown BootLoader on VolGroup-lv_root'


Unknown BootLoader on VolGroup-lv_swap'



=============================== StdErr Messages: ===============================

  One or more specified logical volume(s) not found.
  One or more specified logical volume(s) not found.
  One or more specified logical volume(s) not found.
hexdump: /dev/mapper/VolGroup-lv_root': No such file or directory
hexdump: stdin: Bad file descriptor.
hexdump: /dev/mapper/VolGroup-lv_root': No such file or directory
hexdump: /dev/mapper/VolGroup-lv_root': Bad file descriptor
  One or more specified logical volume(s) not found.
  One or more specified logical volume(s) not found.
  One or more specified logical volume(s) not found.
hexdump: /dev/mapper/VolGroup-lv_swap': No such file or directory
hexdump: stdin: Bad file descriptor.
hexdump: /dev/mapper/VolGroup-lv_swap': No such file or directory
hexdump: /dev/mapper/VolGroup-lv_swap': Bad file descriptor
mdadm: No arrays found in config file or automatically

syg00 · 11-23-2011, 06:04 PM

Dunno - better start looking in your log files (and dmesg). That bootinfoscript just uses the standard commands - even complains if they aren't there.
So that "blkid" output is interesting.

As an aside, the boot doesn't need the /dev/sd?? node definition(s), but to update the (grub) code you'll obviously need to get it mounted.

Paint me as confused (as well).

localgameworld · 11-23-2011, 06:11 PM

I found out the issue. UUID was different from the output of the "blkid" command and in /etc/fstab. Changing the UUID for the boot device to match the output from the blkid command did the trick.
Thanks so much for that bash script. It did the trick.

syg00 · 11-23-2011, 06:28 PM

Yeah I noticed that - doesn't really explain why the mount you issued in post #5 didn't work.
RH are doing something screwy in udev/initscripts.