RAID6 Rebuild Issue - Data Offset possibly
From: Yorik <hidden>
Date: 2014-01-30 14:09:57
Hello
I've been using "mdadm" for about 8-9 years with a lot of success in
different Array configurations. I am a huge fan of Software RAID. I
recently suffered a failure that was very unfortunate and I now have
an issue with differing Data Offset and other issues preventing my
Array from rebuilding. A brief history follows:
Array originally created as RAID5, 3x 3TB Drives in May 2011 on a
(then) latest Fedora build.
Added more drives in 2012 and 2013 with upgraded Fedora builds.
Recently added another drive and changed to RAID6, 6x6TB Drives.
Suffered a failure shortly after 2 more drives that kicked the last 2
drives off and one of the 6 other that were previously running.
During the RAID rebuild, my computer locked up and then suffered a
Power Failure (having a bad day) that stopped my OS Disk (SSD) from
allowing me to reboot. Eventually rebuilt the OS with Fedora 20,
wiping the majority of the SSD and config files with it.
The RAID6 does not start, stating that it only has 5 of the 8 drives
required. Looking into this, the drives seem to be clean and check
okay, but there is even differences (expected) and Data Offset
difference between drives that I read (here:
h__p://neil.brown.name/blog/20120615073245) was not necessarily good
for rebuilding and that I should ask for a version of mdadm that can
handle this as it's possible that creating with an older version, then
adding new drives is causing an issue. Data Offsets of 2048 and 4096
exist.
Also of note is that I have some drives that are on the Array without
partitions as they would not add to the Array with partitions on them
due to size when they were added. I think that I had version issue
with fdisk, but it seemed to work okay until now.
When I run the following command:
mdadm --create --assume-clean --level=6 --raid-devices=8
--size=2930263552 /dev/md0 /dev/sda1 /dev/sdb1 /dev/sdc1 /dev/sdd
/dev/sdi /dev/sde /dev/sdg /dev/sdf
I get:
mdadm: /dev/sda1 is smaller than given size. 2930134016K < 2930263552K
+ metadata
mdadm: /dev/sdb1 is smaller than given size. 2930134016K < 2930263552K
+ metadata
mdadm: /dev/sdc1 is smaller than given size. 2930134016K < 2930263552K
+ metadata
mdadm: /dev/sdd is smaller than given size. 2930135040K < 2930263552K + metadata
mdadm: /dev/sdi is smaller than given size. 2930135040K < 2930263552K + metadata
mdadm: /dev/sde is smaller than given size. 2930135040K < 2930263552K + metadata
mdadm: /dev/sdg is smaller than given size. 2930135040K < 2930263552K + metadata
mdadm: /dev/sdf is smaller than given size. 2930135040K < 2930263552K + metadata
mdadm: create aborted
Which makes me think that there are further issues. Should I be
looking for an older version of mdadm or a different version? Can
anyone offer some advice please or where to look next.
Regards
Derek
Information follows:
--Drive information--
mdadm --examine <Appropriate partitions and drives>
/dev/sda1:
Magic : a92b4efc
Version : 1.1
Feature Map : 0x5
Array UUID : 80009fa3:a96743bd:f5dbfd87:18a1c52d
Name : desktop:0
Creation Time : Tue May 31 01:55:34 2011
Raid Level : raid6
Raid Devices : 8
Avail Dev Size : 5860528128 (2794.52 GiB 3000.59 GB)
Array Size : 17581581312 (16767.10 GiB 18003.54 GB)
Used Dev Size : 5860527104 (2794.52 GiB 3000.59 GB)
Data Offset : 2048 sectors
Super Offset : 0 sectors
Unused Space : before=1976 sectors, after=1024 sectors
State : clean
Device UUID : e27f0cdd:f9ade1a9:069a8d4d:a4e7d767
Internal Bitmap : 8 sectors from superblock
Reshape pos'n : 30978048 (29.54 GiB 31.72 GB)
Delta Devices : 2 (6->8)
Update Time : Tue Jan 21 23:35:32 2014
Checksum : 944933 - correct
Events : 3118496
Layout : left-symmetric
Chunk Size : 512K
Device Role : Active device 0
Array State : AAAA.A.. ('A' == active, '.' == missing, 'R' == replacing)
/dev/sdb1:
Magic : a92b4efc
Version : 1.1
Feature Map : 0x5
Array UUID : 80009fa3:a96743bd:f5dbfd87:18a1c52d
Name : desktop:0
Creation Time : Tue May 31 01:55:34 2011
Raid Level : raid6
Raid Devices : 8
Avail Dev Size : 5860528128 (2794.52 GiB 3000.59 GB)
Array Size : 17581581312 (16767.10 GiB 18003.54 GB)
Used Dev Size : 5860527104 (2794.52 GiB 3000.59 GB)
Data Offset : 2048 sectors
Super Offset : 0 sectors
Unused Space : before=1976 sectors, after=1024 sectors
State : active
Device UUID : ff0ddbdd:5d3123ae:3b813125:97a96017
Internal Bitmap : 8 sectors from superblock
Reshape pos'n : 30978048 (29.54 GiB 31.72 GB)
Delta Devices : 2 (6->8)
Update Time : Tue Jan 21 23:35:32 2014
Checksum : 8cd103dc - correct
Events : 3118496
Layout : left-symmetric
Chunk Size : 512K
Device Role : Active device 1
Array State : AAAA.A.. ('A' == active, '.' == missing, 'R' == replacing)
/dev/sdc1:
Magic : a92b4efc
Version : 1.1
Feature Map : 0x5
Array UUID : 80009fa3:a96743bd:f5dbfd87:18a1c52d
Name : desktop:0
Creation Time : Tue May 31 01:55:34 2011
Raid Level : raid6
Raid Devices : 8
Avail Dev Size : 5860528128 (2794.52 GiB 3000.59 GB)
Array Size : 17581581312 (16767.10 GiB 18003.54 GB)
Used Dev Size : 5860527104 (2794.52 GiB 3000.59 GB)
Data Offset : 2048 sectors
Super Offset : 0 sectors
Unused Space : before=1976 sectors, after=1024 sectors
State : active
Device UUID : f4106804:6552a7b0:2a960408:b7ca41ff
Internal Bitmap : 8 sectors from superblock
Reshape pos'n : 30978048 (29.54 GiB 31.72 GB)
Delta Devices : 2 (6->8)
Update Time : Tue Jan 21 23:35:32 2014
Checksum : 80965de9 - correct
Events : 3118496
Layout : left-symmetric
Chunk Size : 512K
Device Role : Active device 2
Array State : AAAA.A.. ('A' == active, '.' == missing, 'R' == replacing)
/dev/sdd:
Magic : a92b4efc
Version : 1.1
Feature Map : 0x5
Array UUID : 80009fa3:a96743bd:f5dbfd87:18a1c52d
Name : desktop:0
Creation Time : Tue May 31 01:55:34 2011
Raid Level : raid6
Raid Devices : 8
Avail Dev Size : 5860529072 (2794.52 GiB 3000.59 GB)
Array Size : 17581581312 (16767.10 GiB 18003.54 GB)
Used Dev Size : 5860527104 (2794.52 GiB 3000.59 GB)
Data Offset : 4096 sectors
Super Offset : 0 sectors
Unused Space : before=4024 sectors, after=1968 sectors
State : active
Device UUID : d9d26a74:100488a7:8841e37a:f84e07b7
Internal Bitmap : 8 sectors from superblock
Reshape pos'n : 30978048 (29.54 GiB 31.72 GB)
Delta Devices : 2 (6->8)
Update Time : Tue Jan 21 23:35:32 2014
Checksum : 121e0ccb - correct
Events : 3118496
Layout : left-symmetric
Chunk Size : 512K
Device Role : Active device 3
Array State : AAAA.A.. ('A' == active, '.' == missing, 'R' == replacing)
/dev/sde:
Magic : a92b4efc
Version : 1.1
Feature Map : 0x5
Array UUID : 80009fa3:a96743bd:f5dbfd87:18a1c52d
Name : desktop:0
Creation Time : Tue May 31 01:55:34 2011
Raid Level : raid6
Raid Devices : 8
Avail Dev Size : 5860529072 (2794.52 GiB 3000.59 GB)
Array Size : 17581581312 (16767.10 GiB 18003.54 GB)
Used Dev Size : 5860527104 (2794.52 GiB 3000.59 GB)
Data Offset : 4096 sectors
Super Offset : 0 sectors
Unused Space : before=4024 sectors, after=1968 sectors
State : active
Device UUID : a73e6b7b:4791f3d6:b60e1025:0dda98c1
Internal Bitmap : 8 sectors from superblock
Reshape pos'n : 30978048 (29.54 GiB 31.72 GB)
Delta Devices : 2 (6->8)
Update Time : Tue Jan 21 23:35:32 2014
Checksum : fd485e13 - correct
Events : 3118496
Layout : left-symmetric
Chunk Size : 512K
Device Role : Active device 5
Array State : AAAA.A.. ('A' == active, '.' == missing, 'R' == replacing)
/dev/sdf:
Magic : a92b4efc
Version : 1.1
Feature Map : 0x5
Array UUID : 80009fa3:a96743bd:f5dbfd87:18a1c52d
Name : desktop:0
Creation Time : Tue May 31 01:55:34 2011
Raid Level : raid6
Raid Devices : 8
Avail Dev Size : 5860529072 (2794.52 GiB 3000.59 GB)
Array Size : 17581581312 (16767.10 GiB 18003.54 GB)
Used Dev Size : 5860527104 (2794.52 GiB 3000.59 GB)
Data Offset : 4096 sectors
Super Offset : 0 sectors
Unused Space : before=4024 sectors, after=1968 sectors
State : clean
Device UUID : 25acca8d:45ae78df:77d834cb:b97cfadd
Internal Bitmap : 8 sectors from superblock
Reshape pos'n : 30978048 (29.54 GiB 31.72 GB)
Delta Devices : 2 (6->8)
Update Time : Tue Jan 21 23:26:20 2014
Checksum : daba52df - correct
Events : 3118491
Layout : left-symmetric
Chunk Size : 512K
Device Role : Active device 7
Array State : AAAAAAAA ('A' == active, '.' == missing, 'R' == replacing)
/dev/sdg:
Magic : a92b4efc
Version : 1.1
Feature Map : 0x5
Array UUID : 80009fa3:a96743bd:f5dbfd87:18a1c52d
Name : desktop:0
Creation Time : Tue May 31 01:55:34 2011
Raid Level : raid6
Raid Devices : 8
Avail Dev Size : 5860529072 (2794.52 GiB 3000.59 GB)
Array Size : 17581581312 (16767.10 GiB 18003.54 GB)
Used Dev Size : 5860527104 (2794.52 GiB 3000.59 GB)
Data Offset : 4096 sectors
Super Offset : 0 sectors
Unused Space : before=4024 sectors, after=1968 sectors
State : clean
Device UUID : c4fca7c8:450ddd64:41aae795:334c9512
Internal Bitmap : 8 sectors from superblock
Reshape pos'n : 30978048 (29.54 GiB 31.72 GB)
Delta Devices : 2 (6->8)
Update Time : Tue Jan 21 23:26:20 2014
Checksum : 9a49a3c2 - correct
Events : 3118491
Layout : left-symmetric
Chunk Size : 512K
Device Role : Active device 6
Array State : AAAAAAAA ('A' == active, '.' == missing, 'R' == replacing)
/dev/sdi:
Magic : a92b4efc
Version : 1.1
Feature Map : 0x5
Array UUID : 80009fa3:a96743bd:f5dbfd87:18a1c52d
Name : desktop:0
Creation Time : Tue May 31 01:55:34 2011
Raid Level : raid6
Raid Devices : 8
Avail Dev Size : 5860529072 (2794.52 GiB 3000.59 GB)
Array Size : 17581581312 (16767.10 GiB 18003.54 GB)
Used Dev Size : 5860527104 (2794.52 GiB 3000.59 GB)
Data Offset : 4096 sectors
Super Offset : 0 sectors
Unused Space : before=4024 sectors, after=1968 sectors
State : clean
Device UUID : 09f19ee9:414e5ea8:b755a246:a0a2c2f7
Internal Bitmap : 8 sectors from superblock
Reshape pos'n : 30978048 (29.54 GiB 31.72 GB)
Delta Devices : 2 (6->8)
Update Time : Tue Jan 21 23:26:20 2014
Checksum : 94a9dae5 - correct
Events : 3118491
Layout : left-symmetric
Chunk Size : 512K
Device Role : Active device 4
Array State : AAAAAAAA ('A' == active, '.' == missing, 'R' == replacing)
--Device ID's vs Device Name--
lrwxrwxrwx 1 root root 9 Jan 27 23:03
ata-HL-DT-ST_DVDRAM_GH22NS70_K0028Q64636 -> ../../sr0
lrwxrwxrwx 1 root root 9 Jan 27 23:03
ata-OCZ-AGILITY3_OCZ-8D0T42404K8H12P6 -> ../../sdh
lrwxrwxrwx 1 root root 10 Jan 27 23:03
ata-OCZ-AGILITY3_OCZ-8D0T42404K8H12P6-part1 -> ../../sdh1
lrwxrwxrwx 1 root root 10 Jan 27 23:03
ata-OCZ-AGILITY3_OCZ-8D0T42404K8H12P6-part2 -> ../../sdh2
lrwxrwxrwx 1 root root 9 Jan 27 23:03 ata-ST3000VX000-1CU166_Z1F47ATC
-> ../../sdg
lrwxrwxrwx 1 root root 9 Jan 27 23:03 ata-ST3000VX000-1CU166_Z1F49MSQ
-> ../../sdf
lrwxrwxrwx 1 root root 9 Jan 27 23:03 ata-ST3000VX000-1CU166_Z1F49MYJ
-> ../../sdi
lrwxrwxrwx 1 root root 9 Jan 27 23:03 ata-ST3000VX000-9YW166_Z1F13TGY
-> ../../sde
lrwxrwxrwx 1 root root 9 Jan 27 23:03 ata-ST33000651AS_9XK0B9RF -> ../../sdb
lrwxrwxrwx 1 root root 10 Jan 27 23:03 ata-ST33000651AS_9XK0B9RF-part1
-> ../../sdb1
lrwxrwxrwx 1 root root 9 Jan 27 23:03 ata-ST33000651AS_9XK0BR4Q -> ../../sda
lrwxrwxrwx 1 root root 10 Jan 27 23:03 ata-ST33000651AS_9XK0BR4Q-part1
-> ../../sda1
lrwxrwxrwx 1 root root 9 Jan 27 23:03 ata-ST33000651AS_9XK0F087 -> ../../sdc
lrwxrwxrwx 1 root root 10 Jan 27 23:03 ata-ST33000651AS_9XK0F087-part1
-> ../../sdc1
lrwxrwxrwx 1 root root 9 Jan 27 23:03 ata-ST33000651AS_9XK0FEHD -> ../../sdd
lrwxrwxrwx 1 root root 10 Jan 27 23:03 dm-name-vg_desktop-lv_home -> ../../dm-1
lrwxrwxrwx 1 root root 10 Jan 27 23:03 dm-name-vg_desktop-lv_root -> ../../dm-0
lrwxrwxrwx 1 root root 10 Jan 27 23:03
dm-uuid-LVM-gPmDONxd0J5Xzhng4nMgLyJywSvcsrFB1bQOUpSoE0SzQ6kHuvqiMzxpkiH0ZgWJ
-> ../../dm-1
lrwxrwxrwx 1 root root 10 Jan 27 23:03
dm-uuid-LVM-gPmDONxd0J5Xzhng4nMgLyJywSvcsrFBsTxjvh7YlYcmxUryNXlejEsR55sjfh9w
-> ../../dm-0
lrwxrwxrwx 1 root root 9 Jan 27 23:03 wwn-0x5000c5002dae3e0a -> ../../sdb
lrwxrwxrwx 1 root root 10 Jan 27 23:03 wwn-0x5000c5002dae3e0a-part1 ->
../../sdb1
lrwxrwxrwx 1 root root 9 Jan 27 23:03 wwn-0x5000c5002dfdfece -> ../../sdc
lrwxrwxrwx 1 root root 10 Jan 27 23:03 wwn-0x5000c5002dfdfece-part1 ->
../../sdc1
lrwxrwxrwx 1 root root 9 Jan 27 23:03 wwn-0x5000c5002e0ff1ce -> ../../sda
lrwxrwxrwx 1 root root 10 Jan 27 23:03 wwn-0x5000c5002e0ff1ce-part1 ->
../../sda1
lrwxrwxrwx 1 root root 9 Jan 27 23:03 wwn-0x5000c5002e10998c -> ../../sdd
lrwxrwxrwx 1 root root 9 Jan 27 23:03 wwn-0x5000c5004e34e5a2 -> ../../sde
lrwxrwxrwx 1 root root 9 Jan 27 23:03 wwn-0x5000c500657e23a6 -> ../../sdi
lrwxrwxrwx 1 root root 9 Jan 27 23:03 wwn-0x5000c500657e27c4 -> ../../sdf
lrwxrwxrwx 1 root root 9 Jan 27 23:03 wwn-0x5000c500657e2888 -> ../../sdg
lrwxrwxrwx 1 root root 9 Jan 27 23:03 wwn-0x5e83a97f6722d623 -> ../../sdh
lrwxrwxrwx 1 root root 10 Jan 27 23:03 wwn-0x5e83a97f6722d623-part1 ->
../../sdh1
lrwxrwxrwx 1 root root 10 Jan 27 23:03 wwn-0x5e83a97f6722d623-part2 ->
../../sdh2
cat /etc/mdadm.conf
ARRAY /dev/md0 devices=/dev/sda3,/dev/sdb3,/dev/sdc3,/dev/sdd3,/dev/sde3,/dev/sdf3,/dev/sdg3,/dev/sdh3
--Other--
# uname -a
Linux desktop.yorik 3.12.8-300.fc20.x86_64 #1 SMP Thu Jan 16 01:07:50
UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
# mdadm -V
mdadm - v3.3 - 3rd September 2013