Grub rescue blues

[maicol]

I can no longer boot my Dell T100, raid 1, W Server 2008 R2 and debian 8 - I always get to grub rescue.
The problem is that with ls (+ the device + /) the only one that doesn't give an error (hd0,msdos3) only lists: ./ ../ lost+found. I don't know what to set prefix and root to.
I booted from rescatux on a usb and the result of boot-repair is here: http://paste2.org/CFWf6fVn but I can't make much of it.
I still can't boot. I kind of need to get things back into working order!
Thanks in advance for any help.

[Head_on_a_Stick]

As you appear to have a non-UEFI system then you can attempt to re-install the GRUB bootloader to the disk drive.

See http://crunchbang.org/forums/viewtopic.php?id=15351 for instructions.

I'm not familiar with that script but it seems to be saying that the current bootloader is expecting to find grub.cfg on /dev/sda5 but this is swap rather than a root or /boot partition.

[kiyop]

I am not familiar with RAID.
There may be some problem on RAID.

Code: Select all

 => No known boot loader is installed in the MBR of /dev/sda.
 => Grub2 (v2.00) is installed in the MBR of /dev/sdb and looks at sector 1 of 
    the same hard drive for core.img. core.img is at this location and looks 
    for (,msdos5)/boot/grub. It also embeds following components:
    
    modules
    ---------------------------------------------------------------------------
    fshelp ext2 part_msdos biosdisk

(snip by kiyop)

sdb1: __________________________________________________________________________

    File system:       vfat
    Boot sector type:  Unknown
    Boot sector info:  No errors found in the Boot Parameter Block.
    Operating System:  
    Boot files:        /DELLBIO.BIN /DELLRMK.BIN /COMMAND.COM

sdb2: __________________________________________________________________________

    File system:       vfat
    Boot sector type:  Windows XP: FAT32
    Boot sector info:  No errors found in the Boot Parameter Block.
    Operating System:  
    Boot files:        /bootmgr /ntldr

sdb3: __________________________________________________________________________

    File system:       ext4
    Boot sector type:  -
    Boot sector info: 
    Operating System:  
    Boot files:        

sdb4: __________________________________________________________________________

    File system:       Extended Partition
    Boot sector type:  Unknown
    Boot sector info: 

sdb5: __________________________________________________________________________

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

(snip by kiyop)

Disk /dev/sda: 29.8 GiB, 32015679488 bytes, 62530624 sectors

(snip by kiyop)

Disk /dev/sdb: 232.3 GiB, 249376538624 bytes, 487063552 sectors
Units: sectors of 1 * 512 = 512 bytes

(snip by kiyop)

/dev/sdb1    *             63        80,324        80,262   6 FAT16
/dev/sdb2              80,325     3,020,219     2,939,895   b W95 FAT32
/dev/sdb3         265,875,456   478,015,487   212,140,032  83 Linux
/dev/sdb4         478,015,488   487,061,503     9,046,016   f W95 Extended (LBA)
/dev/sdb5         478,017,536   487,061,503     9,043,968  82 Linux swap / Solaris

(snip by kiyop)

/dev/sda1        2016-09-24-10-03-35-00                 iso9660    Rescatux0.40b11
/dev/sda2        F6EB-741A                              vfat       
/dev/sdb1                                               vfat       DellUtility
/dev/sdb2        5074-7940                              vfat       
/dev/sdb3        8033f3aa-fbc9-465d-8fc7-937719316f50   ext4       
/dev/sdb5        21013065-5032-49a7-85aa-5d45f3a1fff6   swap       

(snip by kiyop)

lrwxrwxrwx. 1 root root 10 Sep 29 18:59 scsi-3600508e000000000309fba449c7c8505-part3 -> ../../sdb3

(snip by kiyop)

lrwxrwxrwx. 1 root root 10 Sep 29 18:59 wwn-0x600508e000000000309fba449c7c8505-part3 -> ../../sdb3

(snip by kiyop)

Unknown BootLoader on sdb1

00000000  eb 4a 90 44 65 6c 6c 20  38 2e 30 00 02 04 01 00  |.J.Dell 8.0.....|
00000010  02 00 02 00 00 f8 4f 00  3f 00 ff 00 3f 00 00 00  |......O.?...?...|
00000020  86 39 01 00 80 00 29 00  00 00 00 44 65 6c 6c 55  |.9....)....DellU|
00000030  74 69 6c 69 74 79 46 41  54 31 36 20 20 20 00 00  |tilityFAT16   ..|

(snip by kiyop)

000001d0  4a 00 00 10 c3 44 69 73  6b 20 65 72 72 6f 72 00  |J....Disk error.|
000001e0  4e 6f 20 6c 6f 61 64 65  72 00 44 45 4c 4c 42 49  |No loader.DELLBI|
000001f0  4f 20 42 49 4e 00 00 00  00 00 00 00 00 00 55 aa  |O BIN.........U.|
00000200

Unknown BootLoader on sdb4

00000000  36 9d 4b 9a 74 2b 06 67  28 4c 40 ba b7 ba f5 ad  |6.K.t+.g(L@.....|

(snip by kiyop)

File descriptor 8 (/proc/1685/mounts) leaked on lvs invocation. Parent PID 9958: bash
File descriptor 13 (/tmp/ffiNWHhvB (deleted)) leaked on lvs invocation. Parent PID 9958: bash
File descriptor 63 (pipe:[28765]) leaked on lvs invocation. Parent PID 9958: bash
  No volume groups found
mdadm: No arrays found in config file or automatically

(snip by kiyop)

Warning: The driver descriptor says the physical block size is 2048 bytes, but Linux says it is 512 bytes.
Warning: The driver descriptor says the physical block size is 2048 bytes, but Linux says it is 512 bytes.

(snip by kiyop)

/dev/sdb1: SEC_TYPE="msdos" LABEL="DellUtility" TYPE="vfat" PARTUUID="38000000-01"

(snip by kiyop)

This live-session is not EFI-compatible.
SecureBoot maybe enabled.

(snip by kiyop)

sdb1	: sdb,	not-sepboot,	no-grubenv	nogrub,	no-docgrub,	no-update-grub,	32,	no-boot,	no-os,	is-correct-EFI,	part-has-no-fstab,	part-has-no-fstab,	no-nt,	no-winload,	no-recov-nor-hid,	no-bmgr,	notwinboot,	nopakmgr,	nogrubinstall,	no---usr,	part-has-no-fstab,	not-sep-usr,	standard,	not-far,	/mnt/boot-sav/sdb1.
sdb2	: sdb,	not-sepboot,	no-grubenv	nogrub,	no-docgrub,	no-update-grub,	32,	no-kernel,	no-os,	not--efi--part,	part-has-no-fstab,	part-has-no-fstab,	ntldr,	no-winload,	no-recov-nor-hid,	bootmgr,	notwinboot,	nopakmgr,	nogrubinstall,	no---usr,	part-has-no-fstab,	not-sep-usr,	standard,	not-far,	/mnt/boot-sav/sdb2.
sdb3	: sdb,	maybesepboot,	no-grubenv	nogrub,	no-docgrub,	no-update-grub,	32,	no-boot,	no-os,	not--efi--part,	part-has-no-fstab,	part-has-no-fstab,	no-nt,	no-winload,	no-recov-nor-hid,	no-bmgr,	notwinboot,	nopakmgr,	nogrubinstall,	no---usr,	part-has-no-fstab,	not-sep-usr,	standard,	farbios,	/mnt/boot-sav/sdb3.

(snip by kiyop)

sdb	: not-GPT,	BIOSboot-not-needed,	has-no-EFIpart, 	not-usb,	no-os,	63 sectors * 512 bytes

(snip by kiyop)

Model: Dell VIRTUAL DISK (scsi)
Disk /dev/sdb: 249GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:

Number  Start   End     Size    Type      File system     Flags
1      32.3kB  41.1MB  41.1MB  primary   fat16           boot
2      41.1MB  1546MB  1505MB  primary   fat32
3      136GB   245GB   109GB   primary   ext2
4      245GB   249GB   4632MB  extended                  lba
5      245GB   249GB   4631MB  logical   linux-swap(v1)

=================== parted -lm:

BYT;
/dev/sda:32.0GB:scsi:512:512:unknown:SanDisk Cruzer Edge:;

BYT;
/dev/sdb:249GB:scsi:512:512:msdos:Dell VIRTUAL DISK:;
1:32.3kB:41.1MB:41.1MB:fat16::boot;
2:41.1MB:1546MB:1505MB:fat32::;
3:136GB:245GB:109GB:ext2::;
4:245GB:249GB:4632MB:::lba;
5:245GB:249GB:4631MB:linux-swap(v1)::;

(snip by kiyop)

sdb3     1  0  0         /mnt/boot-sav/sdb3

(snip by kiyop)

/dev/sda1 on /lib/live/mount/medium type iso9660 (ro,noatime)
/dev/loop0 on /lib/live/mount/rootfs/filesystem.squashfs type squashfs (ro,noatime,seclabel)

(snip by kiyop)

/dev/sdb1 on /mnt/boot-sav/sdb1 type vfat (rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=utf8,shortname=mixed,errors=remount-ro)
/dev/sdb2 on /mnt/boot-sav/sdb2 type vfat (rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=utf8,shortname=mixed,errors=remount-ro)
/dev/sdb3 on /mnt/boot-sav/sdb3 type ext4 (rw,relatime,seclabel)

(snip by kiyop)

/dev/sdb3      ext4      100G   24G   72G  25% /mnt/boot-sav/sdb3

The ca. 100GB ext4 partition /dev/sdb3 is mounted on /mnt/boot-sav/sdb3 and df shows 24GB space is used in /dev/sdb3.
Nevertheless,

Code: Select all

ls (hd0,msdos3)/

lists only
./ ../ lost+found
It means there are almost no usual files in "(hd0,msdos3)".
I cannot understand what happened to (hd0,msdos3).
Maybe, there are many files under /lost+found?
You may be able to recover lost files in (hd0,msdos3) by testdisk and/or photorec available on system rescue cd or so.

[maicol]

Thanks Head_on_a_Stick, I followed the crunchbang instructions but got

root@debian:/home/user# mount --bind /dev/pts $TARGET/dev/pts
mount: mount point /media/sdb1/dev/pts does not exist

and similar when trying other devices.

[Head_on_a_Stick]

root@debian:/home/user# mount --bind /dev/pts $TARGET/dev/pts
mount: mount point /media/sdb1/dev/pts does not exist

You need to post *all* of the commands that you entered rather than just the last line.

For example, what did you set $TARGET as?

It looks like you have may used a gvfs mountpoint from a file manager, which you should *not* do.

Also, I completely overlooked the bit in your OP about RAID

I have no experience of RAID and can offer no advice on that subject.

[kiyop]

root@debian:/home/user# mount --bind /dev/pts $TARGET/dev/pts
mount: mount point /media/sdb1/dev/pts does not exist

and similar when trying other devices.

No partition in "other devices" you tried contains /dev/ directory, which I guessed.

As for that "ls (hd0,msdos3)/" shows only "./ ../ /lost+found", maybe Grub2 booted at boot time cannot use necessary Grub2 modules to use the root partition or maybe the files are lost by some accident.

[maicol]

Sorry Head_on_a_Stick, I wasn't clear when I said 'other devices'. Here are my commands

root@debian:/home/user# TARGET=/media/sdb1
root@debian:/home/user# mkdir -p $TARGET
root@debian:/home/user# mount /dev/sdb1 $TARGET
root@debian:/home/user# mount --bind /dev $TARGET/dev
mount: mount point /media/sdb1/dev does not exist
root@debian:/home/user# TARGET=/media/sdb2
root@debian:/home/user# mkdir -p $TARGET
root@debian:/home/user# mount /dev/sdb2 $TARGET
root@debian:/home/user# mount --bind /dev $TARGET/dev
mount: mount point /media/sdb2/dev does not exist
root@debian:/home/user# TARGET=/media/sdb3
root@debian:/home/user# mkdir -p $TARGET
root@debian:/home/user# mount /dev/sdb3 $TARGET
root@debian:/home/user# mount --bind /dev $TARGET/dev
mount: mount point /media/sdb3/dev does not exist
root@debian:/home/user# TARGET=/media/sdb4
root@debian:/home/user# mkdir -p $TARGET
root@debian:/home/user# mount /dev/sdb4 $TARGET
mount: /dev/sdb4 is write-protected, mounting read-only
mount: wrong fs type, bad option, bad superblock on /dev/sdb4,
missing codepage or helper program, or other error

In some cases useful info is found in syslog - try
dmesg | tail or so.
root@debian:/home/user# TARGET=/media/sdb5
root@debian:/home/user# mkdir -p $TARGET
root@debian:/home/user# mount /dev/sdb5 $TARGET
mount: unknown filesystem type 'swap'

(I knew sdb4 and 5 were not candidates.)
Not sure about what you mean with

you have may used a gvfs mountpoint from a file manager

. The box had W Server 2008 on it originally, I added debian 8 later, from a CD.

[kiyop]

The whole results you posted indicate that what I guessed seems to be correct
Try finding files under /lost+found and try recovering lost files by testdisk and/or photorec, or ... cope with RAID failure or so.

[maicol]

Thanks Kiyop, I tried:
- fsck /dev/sdb3 and it found loads of issues
- testdisk to place mbr on /dev/sdb1 and now I always boot into Dell Utility, I ran the complete test and it passed everything
- testdisk to recover files to no avail.

I'll try photorec when I get the chance.
If that fails I was thinking of disabling RAID, starting from scratch only installing Debian, limiting Windows to a virtual machine. If it was the SAS 6/iR card that originated the problems though I would prefer bypassing it.

[kiyop]

RAID 1 is "mirroring", thus you may be able to recover lost files from one of two HDDs. But I am not familiar with RAID, thus I may be wrong.

"fsck" is last thing I would try in order to recover lost files.
If I were you, I would have learned about RAID1 used in the server and have tried to find some way to recover files.
Then, I would have used ddrescue or so to copy whole of /dev/sdb3 to another media.
Then, I would have used photorec to recover lost files from copied media.
Then, I would have used testdisk to correct partition table of the original media.

I sometimes back-up all the necessary files and directories to another partition in another media, because media like hard disk or usb thumb go wrong.

[maicol]

Thanks for the advice kiyop.
I looked into recovering lost files with the RAID interface available (BIOS) with no luck.
I used photorec to recover lost files (56 GB) to another usb connected HD.
I didn't succeed in using testdisk to correct the partition table.

I then rebooted and disabled RAID, rebooted into a USB stick with a debian net iso, placing debian on /dev/sda. The other HD (/dev/sdb) still shows the previous partitions with fdisk -l. Now I only need to sift through 800.000+ files to see if there is something I can make use of!

Thanks.