I just checked into my RAID array this morning and what I got is:
$ cat /proc/mdstat
Personalities : [raid1] [linear] [multipath] [raid0] [raid6] [raid5] [raid4] [raid10]
md1 : active raid1 sdc7[0]
238340224 blocks [2/1] [U_]
md0 : active raid1 sdc6[0]
244139648 blocks [2/1] [U_]
md127 : active raid1 sdc3[0]
390628416 blocks [2/1] [U_]
unused devices: <none>
$
Which, I believe, means that one disk of my array(s) is dead, is this true?
How do I do proper troubleshooting going forward?
My /etc/mdadm/mdadm.conf
looks like:
$ cat /etc/mdadm/mdadm.conf
# mdadm.conf
#
# Please refer to mdadm.conf(5) for information about this file.
#
# by default (built-in), scan all partitions (/proc/partitions) and all
# containers for MD superblocks. alternatively, specify devices to scan, using
# wildcards if desired.
#DEVICE partitions containers
# auto-create devices with Debian standard permissions
CREATE owner=root group=disk mode=0660 auto=yes
# automatically tag new arrays as belonging to the local system
HOMEHOST <system>
# instruct the monitoring daemon where to send mail alerts
MAILADDR root
# definitions of existing MD arrays
ARRAY /dev/md127 UUID=124cd4a5:2965955f:cd707cc0:bc3f8165
ARRAY /dev/md0 UUID=91e560f1:4e51d8eb:cd707cc0:bc3f8165
ARRAY /dev/md1 UUID=0abe503f:401d8d09:cd707cc0:bc3f8165
How do I find out which physical drive is broken and needs to be replaced?
Thanks
EDIT1
# mdadm --detail /dev/md0
/dev/md0:
Version : 0.90
Creation Time : Tue Sep 1 19:15:33 2009
Raid Level : raid1
Array Size : 244139648 (232.83 GiB 250.00 GB)
Used Dev Size : 244139648 (232.83 GiB 250.00 GB)
Raid Devices : 2
Total Devices : 1
Preferred Minor : 0
Persistence : Superblock is persistent
Update Time : Mon Sep 21 07:11:24 2015
State : clean, degraded
Active Devices : 1
Working Devices : 1
Failed Devices : 0
Spare Devices : 0
UUID : 91e560f1:4e51d8eb:cd707cc0:bc3f8165
Events : 0.76017
Number Major Minor RaidDevice State
0 8 38 0 active sync /dev/sdc6
1 0 0 1 removed
root@regDesktopHome:~#
Why would it say Failed Devices : 0
?
EDIT2
Opening Gparted, I can look at both, /dev/sdb
& /dev/sdc
which were my two RAID
drives. However, mdadm thinks /dev.sdb
has been removed for some reason… that's odd.
I tried to mount a partition on “/dev/sdb` and got the following
$sudo mount /dev/sdb7 test
[sudo] password for ron:
mount: unknown filesystem type 'linux_raid_member'
which looks all coorect. How do I get my RAID array back in order?
EDIT 3
I ran smartctl -a /dev/sdc
and smartctl -a /dev/sdb
, I also did badblocks /dev/sdc
and badblocks /dev/sdb
and while sdc
seems 100% clean, sdb
returned some bad blocks:
# badblocks /dev/sdb
16130668
16130669
16130670
16130671
Would that potentially be the cause for the fault I'm seeing? Any way to repair/ignore these bad blocks or should I replace the drive instead?
EDIT 4
# smartctl --all /dev/sdb
smartctl 6.2 2013-07-26 r3841 [x86_64-linux-3.13.0-62-generic] (local build)
Copyright (C) 2002-13, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF INFORMATION SECTION ===
Model Family: Seagate Barracuda 7200.12
Device Model: ST31000528AS
Serial Number: 6VP0308B
LU WWN Device Id: 5 000c50 013d3ae45
Firmware Version: CC34
User Capacity: 1,000,204,886,016 bytes [1.00 TB]
Sector Size: 512 bytes logical/physical
Rotation Rate: 7200 rpm
Device is: In smartctl database [for details use: -P show]
ATA Version is: ATA8-ACS T13/1699-D revision 4
SATA Version is: SATA 2.6, 3.0 Gb/s
Local Time is: Sat Sep 26 11:35:02 2015 PDT
==> WARNING: A firmware update for this drive may be available,
see the following Seagate web pages:
http://knowledge.seagate.com/articles/en_US/FAQ/207931en
http://knowledge.seagate.com/articles/en_US/FAQ/213891en
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED
General SMART Values:
Offline data collection status: (0x82) Offline data collection activity
was completed without error.
Auto Offline Data Collection: Enabled.
Self-test execution status: ( 0) The previous self-test routine completed
without error or no self-test has ever
been run.
Total time to complete Offline
data collection: ( 600) seconds.
Offline data collection
capabilities: (0x7b) SMART execute Offline immediate.
Auto Offline data collection on/off support.
Suspend Offline collection upon new
command.
Offline surface scan supported.
Self-test supported.
Conveyance Self-test supported.
Selective Self-test supported.
SMART capabilities: (0x0003) Saves SMART data before entering
power-saving mode.
Supports SMART auto save timer.
Error logging capability: (0x01) Error logging supported.
General Purpose Logging supported.
Short self-test routine
recommended polling time: ( 1) minutes.
Extended self-test routine
recommended polling time: ( 195) minutes.
Conveyance self-test routine
recommended polling time: ( 2) minutes.
SCT capabilities: (0x103f) SCT Status supported.
SCT Error Recovery Control supported.
SCT Feature Control supported.
SCT Data Table supported.
SMART Attributes Data Structure revision number: 10
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE
1 Raw_Read_Error_Rate 0x000f 114 099 006 Pre-fail Always - 78420742
3 Spin_Up_Time 0x0003 095 095 000 Pre-fail Always - 0
4 Start_Stop_Count 0x0032 099 099 020 Old_age Always - 1240
5 Reallocated_Sector_Ct 0x0033 099 099 036 Pre-fail Always - 60
7 Seek_Error_Rate 0x000f 082 060 030 Pre-fail Always - 199357441
9 Power_On_Hours 0x0032 052 052 000 Old_age Always - 42401
10 Spin_Retry_Count 0x0013 100 100 097 Pre-fail Always - 0
12 Power_Cycle_Count 0x0032 099 037 020 Old_age Always - 1240
183 Runtime_Bad_Block 0x0000 098 098 000 Old_age Offline - 2
184 End-to-End_Error 0x0032 100 100 099 Old_age Always - 0
187 Reported_Uncorrect 0x0032 094 094 000 Old_age Always - 6
188 Command_Timeout 0x0032 100 100 000 Old_age Always - 0
189 High_Fly_Writes 0x003a 050 050 000 Old_age Always - 50
190 Airflow_Temperature_Cel 0x0022 062 046 045 Old_age Always - 38 (Min/Max 30/38)
194 Temperature_Celsius 0x0022 038 054 000 Old_age Always - 38 (0 17 0 0 0)
195 Hardware_ECC_Recovered 0x001a 030 012 000 Old_age Always - 78420742
197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 1
198 Offline_Uncorrectable 0x0010 100 100 000 Old_age Offline - 1
199 UDMA_CRC_Error_Count 0x003e 200 200 000 Old_age Always - 0
240 Head_Flying_Hours 0x0000 100 253 000 Old_age Offline - 73332271657814
241 Total_LBAs_Written 0x0000 100 253 000 Old_age Offline - 2822963046
242 Total_LBAs_Read 0x0000 100 253 000 Old_age Offline - 2361465529
SMART Error Log Version: 1
ATA Error Count: 6 (device log contains only the most recent five errors)
CR = Command Register [HEX]
FR = Features Register [HEX]
SC = Sector Count Register [HEX]
SN = Sector Number Register [HEX]
CL = Cylinder Low Register [HEX]
CH = Cylinder High Register [HEX]
DH = Device/Head Register [HEX]
DC = Device Command Register [HEX]
ER = Error register [HEX]
ST = Status register [HEX]
Powered_Up_Time is measured from power on, and printed as
DDd+hh:mm:SS.sss where DD=days, hh=hours, mm=minutes,
SS=sec, and sss=millisec. It "wraps" after 49.710 days.
Error 6 occurred at disk power-on lifetime: 42372 hours (1765 days + 12 hours)
When the command that caused the error occurred, the device was active or idle.
After command completion occurred, registers were:
ER ST SC SN CL CH DH
-- -- -- -- -- -- --
40 51 00 d9 44 ec 01 Error: UNC at LBA = 0x01ec44d9 = 32261337
Commands leading to the command that caused the error were:
CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name
-- -- -- -- -- -- -- -- ---------------- --------------------
60 00 08 d8 44 ec 41 00 09:26:28.967 READ FPDMA QUEUED
27 00 00 00 00 00 e0 00 09:26:28.941 READ NATIVE MAX ADDRESS EXT [OBS-ACS-3]
ec 00 00 00 00 00 a0 00 09:26:28.940 IDENTIFY DEVICE
ef 03 46 00 00 00 a0 00 09:26:28.928 SET FEATURES [Set transfer mode]
27 00 00 00 00 00 e0 00 09:26:28.901 READ NATIVE MAX ADDRESS EXT [OBS-ACS-3]
Error 5 occurred at disk power-on lifetime: 42372 hours (1765 days + 12 hours)
When the command that caused the error occurred, the device was active or idle.
After command completion occurred, registers were:
ER ST SC SN CL CH DH
-- -- -- -- -- -- --
40 51 00 d9 44 ec 01 Error: UNC at LBA = 0x01ec44d9 = 32261337
Commands leading to the command that caused the error were:
CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name
-- -- -- -- -- -- -- -- ---------------- --------------------
60 00 08 d8 44 ec 41 00 09:26:26.095 READ FPDMA QUEUED
27 00 00 00 00 00 e0 00 09:26:26.069 READ NATIVE MAX ADDRESS EXT [OBS-ACS-3]
ec 00 00 00 00 00 a0 00 09:26:26.068 IDENTIFY DEVICE
ef 03 46 00 00 00 a0 00 09:26:26.055 SET FEATURES [Set transfer mode]
27 00 00 00 00 00 e0 00 09:26:26.029 READ NATIVE MAX ADDRESS EXT [OBS-ACS-3]
Error 4 occurred at disk power-on lifetime: 42372 hours (1765 days + 12 hours)
When the command that caused the error occurred, the device was active or idle.
After command completion occurred, registers were:
ER ST SC SN CL CH DH
-- -- -- -- -- -- --
40 51 00 d9 44 ec 01 Error: UNC at LBA = 0x01ec44d9 = 32261337
Commands leading to the command that caused the error were:
CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name
-- -- -- -- -- -- -- -- ---------------- --------------------
60 00 08 d8 44 ec 41 00 09:26:23.222 READ FPDMA QUEUED
27 00 00 00 00 00 e0 00 09:26:23.195 READ NATIVE MAX ADDRESS EXT [OBS-ACS-3]
ec 00 00 00 00 00 a0 00 09:26:23.194 IDENTIFY DEVICE
ef 03 46 00 00 00 a0 00 09:26:23.182 SET FEATURES [Set transfer mode]
27 00 00 00 00 00 e0 00 09:26:23.137 READ NATIVE MAX ADDRESS EXT [OBS-ACS-3]
Error 3 occurred at disk power-on lifetime: 42372 hours (1765 days + 12 hours)
When the command that caused the error occurred, the device was active or idle.
After command completion occurred, registers were:
ER ST SC SN CL CH DH
-- -- -- -- -- -- --
40 51 00 d9 44 ec 01 Error: UNC at LBA = 0x01ec44d9 = 32261337
Commands leading to the command that caused the error were:
CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name
-- -- -- -- -- -- -- -- ---------------- --------------------
60 00 08 d8 44 ec 41 00 09:26:20.351 READ FPDMA QUEUED
60 00 80 e8 44 ec 41 00 09:26:20.350 READ FPDMA QUEUED
27 00 00 00 00 00 e0 00 09:26:20.324 READ NATIVE MAX ADDRESS EXT [OBS-ACS-3]
ec 00 00 00 00 00 a0 00 09:26:20.323 IDENTIFY DEVICE
ef 03 46 00 00 00 a0 00 09:26:20.311 SET FEATURES [Set transfer mode]
Error 2 occurred at disk power-on lifetime: 42372 hours (1765 days + 12 hours)
When the command that caused the error occurred, the device was active or idle.
After command completion occurred, registers were:
ER ST SC SN CL CH DH
-- -- -- -- -- -- --
40 51 00 d9 44 ec 01 Error: UNC at LBA = 0x01ec44d9 = 32261337
Commands leading to the command that caused the error were:
CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name
-- -- -- -- -- -- -- -- ---------------- --------------------
60 00 80 e8 44 ec 41 00 09:26:17.478 READ FPDMA QUEUED
60 00 40 a8 44 ec 41 00 09:26:17.478 READ FPDMA QUEUED
60 00 20 88 44 ec 41 00 09:26:17.476 READ FPDMA QUEUED
60 00 08 80 44 ec 41 00 09:26:17.453 READ FPDMA QUEUED
27 00 00 00 00 00 e0 00 09:26:17.427 READ NATIVE MAX ADDRESS EXT [OBS-ACS-3]
SMART Self-test log structure revision number 1
No self-tests have been logged. [To run self-tests, use: smartctl -t]
SMART Selective self-test log data structure revision number 1
SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS
1 0 0 Not_testing
2 0 0 Not_testing
3 0 0 Not_testing
4 0 0 Not_testing
5 0 0 Not_testing
Selective self-test flags (0x0):
After scanning selected spans, do NOT read-scan remainder of disk.
If Selective self-test is pending on power-up, resume after 0 minute delay.
#
EDIT 5
I realized that after unplugging /dev/sdb
, previous /dev/sdc
is now /dev/sdb
. I confirmed with smartctl -a /dev/sdb
that the serial number has changed after booting with the bad disk unplugged. I'm unlucky and the drive is out of warranty, so I will get myself a new replacement drive.
Best Answer
Seeing as how you don't see the broken drive (marked with F) in the output of
cat /proc/mdstat
, you have booted the server since the array was degraded.You can obtain info with
mdadm --detail /dev/md0
. That will probably tell you which other drive should be in it.To respond to your edit:
I would analyze
/dev/sdb
first. Usesmartctl -a
to check (especially) the reallocated sector count and the error log. Do a self test withsmartctl -t long /dev/sdb
. Usebadblocks
, etc.Then:
/dev/sdb
, copy the partition table from/dev/sdc
. If they're not GPT, you can usesfdisk -d /dev/sdc | sfdisk /dev/sdb
. Or if they are GPT, you can usegdisk
to save the partition table to file, and then load it. It's hidden under advanced functions./dev/sdb
, you may want to runmdadm --zero-superblock
on all existing partitions.mdadm --manage /dev/md0 --add /dev/sdb6
and the same formd1
andsdb7
Needless to say, some commands wipe out your data if you mix up your drives. So, be sure what is
sdc
andsdb
...Edit: about bad blocks: If any software level tool sees badblocks, the drive is busted. Normally, disks hide them by reallocating them transparantly upon write. Google for 'hard drive sector reallocation'. Your
smartctl -a
output should show reallocated sectors forsdb
. So yeah, yoursdb
has been kicked out of the array and you need to replace it.Edit: about the
smartctl -a
output. There are two things in there that are of primary importance:smartd
to monitor it for you.Power on hours
. There are harmless things that can cause SMART error log entries, like giving wrong ATA commands, but in this case, because you have a degraded array, it's likely they are related.As for determining which disk it is in your system; for example, doing
dmesg |grep -i sdb
will help. You probably have three disks in your system andsdb
is the one on your second SATA controller, which can be named 1 or 2, depending if it's zero-based or one-based.Because you likely boot from
sda
, you can just replacesdb
and perform the operations I outlined above. If your boot drive is broken, you hope that you have:The other day with a Dell server, it didn't want to start from
sdb
when there was a blanksda
in it. That took some convincing and improvising.Sometimes you need to translate names like
ata1.01
to real device names. For example, failing disks will give kernel errors saying 'ATA exception on ata1.01' or words to that effect. Read this answer for that. (I configured our central logging system to warn me of those kernel errors, because they are a reliable indication of pending disk failure).