I have ubuntu 18.04.2 based server with Software based RAID5 partition for Data. After rebooting the system. It is unable to mount automatically. When I try to mount using command "sudo mount -a". I get following error.
mount: wrong fs type, bad option, bad superblock on /dev/md0,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so.
dmesg | tail command out is as following
[ 45.596679] Bridge firewalling registered
[ 45.628950] nf_conntrack version 0.5.0 (65536 buckets, 262144 max)
[ 45.712031] ip_tables: (C) 2000-2006 Netfilter Core Team
[ 45.765630] Initializing XFRM netlink socket
[ 45.772559] Netfilter messages via NETLINK v0.30.
[ 45.774814] ctnetlink v0.93: registering with nfnetlink.
[ 45.944103] IPv6: ADDRCONF(NETDEV_UP): docker0: link is not ready
[ 46.792337] aufs au_opts_verify:1597:dockerd[2191]: dirperm1 breaks the protection by the permission bits on the lower branch
[ 75.420002] EXT4-fs (md0): can't read group descriptor 5242
[ 605.733833] EXT4-fs (md0): can't read group descriptor 5242
Output of mdadm --detail /dev/md0
is as following
dev/md0:
Version : 1.2
Creation Time : Sun Jan 6 20:39:33 2002
Raid Level : raid5
Array Size : 46883119104 (44711.23 GiB 48008.31 GB)
Used Dev Size : 5860389888 (5588.90 GiB 6001.04 GB)
Raid Devices : 9
Total Devices : 8
Persistence : Superblock is persistent
Intent Bitmap : Internal
Update Time : Fri Jun 7 09:19:58 2019
State : clean, degraded
Active Devices : 8
Working Devices : 8
Failed Devices : 0
Spare Devices : 0
Layout : left-symmetric
Chunk Size : 512K
Name : ubuntu:0 (local to host ubuntu)
UUID : e5109f94:e146b6d5:686e76d7:36787295
Events : 869392
Number Major Minor RaidDevice State
0 8 33 0 active sync /dev/sdc1
1 8 49 1 active sync /dev/sdd1
2 8 65 2 active sync /dev/sde1
3 8 81 3 active sync /dev/sdf1
8 0 0 8 removed
5 8 113 5 active sync /dev/sdh1
6 8 129 6 active sync /dev/sdi1
7 8 145 7 active sync /dev/sdj1
8 8 161 8 active sync /dev/sdk1
Output for fsck /dev/md0
fsck from util-linux 2.27.1
e2fsck 1.42.13 (17-May-2015)
fsck.ext4: Attempt to read block from filesystem resulted in short read while trying to open /dev/md0
Could this be a zero-length partition?
Output for mke2fs -n /dev/sdg1
mke2fs 1.42.13 (17-May-2015)
/dev/sdg1 contains a linux_raid_member file system labelled 'ubuntu:0'
Proceed anyway? (y,n) y
Creating filesystem with 1465130240 4k blocks and 183144448 inodes
Filesystem UUID: f2f50279-73b6-4d89-9251-e5056ace74de
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,
102400000, 214990848, 512000000, 550731776, 644972544
Please help.
Thank you