I am running Debian 9 with mdadm
RAID 1 on it. Previously both hard-drives could boot into the OS, now only one of them can.
I have recently had a faulty disk which needed to be replaced, so replace it I did.
First, I ran
mdadm --add /dev/md0 /dev/sda
Which worked well. Right after that I ran
grub-install /dev/sda
Which gave me the following output:
Installing for i386-pc platform.
grub-install: warning: Couldn't find physical volume `(null)'. Some modules may be missing from core image..
grub-install: error: unable to identify a filesystem in hd0; safety check can't be performed.
Here is my output from lsblk
:
sda 8:0 0 447.1G 0 disk
└─md0 9:0 0 232.8G 0 raid1
├─md0p1 259:0 0 14.9G 0 md [SWAP]
├─md0p2 259:1 0 1K 0 md
├─md0p3 259:2 0 216G 0 md /
└─md0p5 259:3 0 1.9G 0 md /boot
sdb 8:16 0 5.5T 0 disk
├─sdb1 8:17 0 5.5T 0 part
└─sdb9 8:25 0 8M 0 part
sdc 8:32 0 5.5T 0 disk
├─sdc1 8:33 0 5.5T 0 part
└─sdc9 8:41 0 8M 0 part
sdd 8:48 0 232.9G 0 disk
└─sdd1 8:49 0 232.9G 0 part
└─md0 9:0 0 232.8G 0 raid1
├─md0p1 259:0 0 14.9G 0 md [SWAP]
├─md0p2 259:1 0 1K 0 md
├─md0p3 259:2 0 216G 0 md /
└─md0p5 259:3 0 1.9G 0 md /boot
And here is the output from mdadm --detail /dev/md0
:
/dev/md0:
Version : 1.2
Creation Time : Wed Dec 12 15:26:35 2018
Raid Level : raid1
Array Size : 244066304 (232.76 GiB 249.92 GB)
Used Dev Size : 244066304 (232.76 GiB 249.92 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent
Intent Bitmap : Internal
Update Time : Thu May 28 18:59:51 2020
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0
Name : localserver:0 (local to host localserver)
UUID : 83d5a386:66110e10:e5f3c600:734423a8
Events : 5339803
Number Major Minor RaidDevice State
2 8 0 0 active sync /dev/sda
1 8 49 1 active sync /dev/sdd1
I have tried booting with just /dev/sda
, but to no avail. I have also tried running blockdev --flushbufs /dev/sda
, as recommended by some, but to no avail.
When running GParted I can see that /dev/sdd1
has the flags boot and raid, while /dev/sda
has none. I also see there that /dev/sda
's first sector starts at 0, while /dev/sdd1
's starts at 2048.
Can anyone suggest a way I can solve this?
I don't mind detaching the "weird" hard-drive, formatting it, and reattaching it.