Install failes after md raid replace

[Tobias Lang]

Hi everybody,

after the replacement of a faulty disk in a md raid setup (Raid 1), we
are not able to update grub.

The system is an Ubuntu 12.04.5 LTS, with the latests patches installed,
and running Linux version 3.2.0-95-generic (address@hidden).

Disk replacement procedure involved the following steps:

# sgdisk -R /dev/sda /dev/sdb
# sgdisk -G /dev/sda
# mdadm /dev/mdX -a /dev/sdbX

After resync, this failes:

# grub-mkdevicemap -n
# grub-install /dev/sda
  /usr/sbin/grub-probe: error: unknown filesystem.
  Auto-detection of a filesystem of /dev/md1 failed.
  Try with --recheck.

Below is the output of the suggested command.

Sadly I could not find any helpful clues while using my favorite search
engine. Any help is appreciated.

Best regards,

Tobias

-----------------------------------------------------------------------
# /usr/sbin/grub-probe --device-map="/boot/grub/device.map" --target=fs
-v /boot/grub
/usr/sbin/grub-probe: info: Scanning for dmraid_nv RAID devices on disk hd0.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for dmraid_nv RAID devices on disk hd1.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: scanning hd0 for LVM.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: scanning hd1 for LVM.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk hd0.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk hd1.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk hd0.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk hd1.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk hd0.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk
hd0,gpt5.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk
hd0,gpt4.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk
hd0,gpt3.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk
hd0,gpt2.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk
hd0,gpt1.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk hd1.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk
hd1,gpt5.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk
hd1,gpt4.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk
hd1,gpt3.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk
hd1,gpt2.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid09 RAID devices on disk
hd1,gpt1.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk hd0.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk
hd0,gpt5.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk
hd0,gpt4.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk
hd0,gpt3.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk
hd0,gpt2.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Found array md/1 (mdraid1x).
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk
hd0,gpt1.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk hd1.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk
hd1,gpt5.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk
hd1,gpt4.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Found array md/3 (mdraid1x).
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk
hd1,gpt3.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Found array md/2 (mdraid1x).
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk
hd1,gpt2.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Scanning for mdraid1x RAID devices on disk
hd1,gpt1.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: Found array md/0 (mdraid1x).
/usr/sbin/grub-probe: info: scanning md/0 for LVM.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning md/2 for LVM.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning md/3 for LVM.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning md/1 for LVM.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning hd0 for LVM.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: scanning hd0,gpt5 for LVM.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning hd0,gpt4 for LVM.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning hd0,gpt3 for LVM.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning hd0,gpt2 for LVM.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning hd0,gpt1 for LVM.
/usr/sbin/grub-probe: info: the size of hd0 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning hd1 for LVM.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: scanning hd1,gpt5 for LVM.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning hd1,gpt4 for LVM.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning hd1,gpt3 for LVM.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning hd1,gpt2 for LVM.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: scanning hd1,gpt1 for LVM.
/usr/sbin/grub-probe: info: the size of hd1 is 5860533168.
/usr/sbin/grub-probe: info: no LVM signature found.
/usr/sbin/grub-probe: info: opening mduuid/e2d33759fdee07e488ff5b2af57f13ed.
/usr/sbin/grub-probe: error: unknown filesystem.