Raid 6 Fail Event

Raid 6 Fail Event

[Justin Stephenson]

Hello,

I am new to MDADM and have just experienced my first device fail on my 
raid 6.

I am wondering if someone might be able to help by outlining a proper 
protocol for troubleshooting and rebuilding this array (proc/mdstat 
below).

Here is how I might approach it:

- remove the device
- test the device
- if the device tests OK then re add the device
- if the device fails, then replace the device
- resync

Thank-you for your consideration.

Best,

- Justin

Here is the mdstat email

-----------------

This is an automatically generated mail message from mdadm
running on BigBlue

A Fail event had been detected on md device /dev/md0.

It could be related to component device /dev/sdh1.

Faithfully yours, etc.

P.S. The /proc/mdstat file currently contains the following:

Personalities : [raid6] [raid5] [raid4]
md0 : active raid6 sdh1[5](F) sdg1[4] sdf1[3] sde1[2] sdd1[1] sdb1[6] 
sdc1[0]
14650666880 blocks super 1.2 level 6, 128k chunk, algorithm 2 [7/6] 
[UUUUU_U]

unused devices: <none>


--------
Justin Stephenson
Creative Director/Motion Designer
416-900-6069
http://justinstephenson.com

Re: Raid 6 Fail Event

[Chris Murphy]

On Nov 16, 2014, at 8:39 AM, Justin Stephenson <justin@evensteveninc.com> wrote:

> Hello,
> 
> I am new to MDADM and have just experienced my first device fail on my raid 6.
> 
> I am wondering if someone might be able to help by outlining a proper protocol for troubleshooting and rebuilding this array (proc/mdstat below).
> 
> Here is how I might approach it:
> 
> - remove the device
> - test the device
> - if the device tests OK then re add the device
> - if the device fails, then replace the device
> - resync
> 
> Thank-you for your consideration.
> 
> Best,
> 
> - Justin
> 
> Here is the mdstat email
> 
> -----------------
> 
> This is an automatically generated mail message from mdadm
> running on BigBlue
> 
> A Fail event had been detected on md device /dev/md0.
> 
> It could be related to component device /dev/sdh1.

First step is getting the backup current. 

Second you can do this without removing the device:

# smartctl -x /dev/sdh

And then look in dmesg for errors related to its ata designation. You should be able to get a serial number from the smartctl output and can search that with dmesg | grep <serial#> to find out what it’s ata designation (port and device number) is, then you can dmesg | grep ataX.YY to get any read/write error events that explain what’s going on. 

While you’re at it the following would be helpful as well:

# smartctl -l scterc /dev/sdh
# cat /sys/block/sdh/device/state
# cat /sys/block/sdh/device/timeout

These are read-only commands to determine states, they don’t change states so it’s safe.

Chris Murphy--
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Re[2]: Raid 6 Fail Event

[Justin Stephenson]

Thank-you, Chris. I appreciate your help with this.

Backup are good. I'm a regular disk to disk to LTO guy. Here is what I 
have turned up:

================================
# smartctl -x /dev/sdh

big long list of stuff. I found the serial.

I also tried smartctl -H /dev/sdh and received

Overall-health self-assesment test restul: PASSED

184 End-to-End_Error {flag value worst thresh} Old_age FAILING_NOW_6

I did not find anything for the serial in results from dmesg

# smartctl -l scterc /dev/sdh

Warning: device does not support SCT Commands

# cat /sys/block/sdh/device/state

Running

# cat /sys/block/sdh/device/timeout

30

================================

Should I replace the drive or re add and resync?

I also went through and reseated all the SATA and power connections as I 
understand these can cause issues as well.

Best,

- J


------ Original Message ------
From: "Chris Murphy" <lists@colorremedies.com>
To: "Justin Stephenson" <justin@evensteveninc.com>
Cc: linux-raid@vger.kernel.org
Sent: 16/11/2014 2:52:02 PM
Subject: Re: Raid 6 Fail Event

>
>On Nov 16, 2014, at 8:39 AM, Justin Stephenson 
><justin@evensteveninc.com> wrote:
>
>>  Hello,
>>
>>  I am new to MDADM and have just experienced my first device fail on 
>>my raid 6.
>>
>>  I am wondering if someone might be able to help by outlining a proper 
>>protocol for troubleshooting and rebuilding this array (proc/mdstat 
>>below).
>>
>>  Here is how I might approach it:
>>
>>  - remove the device
>>  - test the device
>>  - if the device tests OK then re add the device
>>  - if the device fails, then replace the device
>>  - resync
>>
>>  Thank-you for your consideration.
>>
>>  Best,
>>
>>  - Justin
>>
>>  Here is the mdstat email
>>
>>  -----------------
>>
>>  This is an automatically generated mail message from mdadm
>>  running on BigBlue
>>
>>  A Fail event had been detected on md device /dev/md0.
>>
>>  It could be related to component device /dev/sdh1.
>
>First step is getting the backup current.
>
>Second you can do this without removing the device:
>
># smartctl -x /dev/sdh
>
>And then look in dmesg for errors related to its ata designation. You 
>should be able to get a serial number from the smartctl output and can 
>search that with dmesg | grep <serial#> to find out what it’s ata 
>designation (port and device number) is, then you can dmesg | grep 
>ataX.YY to get any read/write error events that explain what’s going 
>on.
>
>While you’re at it the following would be helpful as well:
>
># smartctl -l scterc /dev/sdh
># cat /sys/block/sdh/device/state
># cat /sys/block/sdh/device/timeout
>
>These are read-only commands to determine states, they don’t change 
>states so it’s safe.
>
>Chris Murphy

--
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the body of a message to majordomo@vger.kernel.org
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Re: Raid 6 Fail Event

[Chris Murphy]

On Nov 16, 2014, at 6:34 PM, Justin Stephenson <justin@evensteveninc.com> wrote:

> Thank-you, Chris. I appreciate your help with this.
> 
> Backup are good. I'm a regular disk to disk to LTO guy. Here is what I have turned up:
> 
> ================================
> # smartctl -x /dev/sdh
> 
> big long list of stuff.

Please post it.



> I found the serial.
> 
> I also tried smartctl -H /dev/sdh and received
> 
> Overall-health self-assesment test restul: PASSED
> 
> 184 End-to-End_Error {flag value worst thresh} Old_age FAILING_NOW_6

Cute, it’s failing but it’s overall health is passing. This is a great example of why the health self-assess is useless.


> 
> I did not find anything for the serial in results from dmesg
> 
> # smartctl -l scterc /dev/sdh
> 
> Warning: device does not support SCT Commands

Interesting it supports a SMART IV attribut but doesn’t support SCT commands.


> 
> # cat /sys/block/sdh/device/state
> 
> Running
> 
> # cat /sys/block/sdh/device/timeout
> 
> 30

Since the drives you have don’t support SCT commands, you need to set the command timer to something much more than the default of 30, otherwise your array will not function correctly when it encounters bad sectors. In many cases the linux scsi command timer will reach 30 seconds and reset the interface, before the typical consumer drive recovers (either returns data successfully or an error). This could be quite long, maybe 2 minutes. Future drives you buy should have configurable SCT ERC so the drive can be set to return a read error after something like 7 seconds, i.e. you want the drive to give up sooner, and by informing md of the problem sector range, the data is rebuilt from parity and written back to the bad sectors on the drive where the problem gets fixed.




> 
> ================================
> 
> Should I replace the drive or re add and resync?

Well I don’t know anything about attribute 184 End-to-End error, but based on the description in wikipedia it sounds disqualifying to me.

I personally would get the drive replaced no matter what: either under warranty, or if no warranty I’d get a new drive and test/play with this one offline and if it proves its worth then maybe it can be a spare down the road.

But you could also smartctl -x all the other drives and see what value they have for this attribute.

> 
> I also went through and reseated all the SATA and power connections as I understand these can cause issues as well.




Chris Murphy--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re[2]: Raid 6 Fail Event

[Justin Stephenson]

Hello Chris,


I have read up on the SMART error the drive has been giving me. It is a 
known issue with the SEAGATE 3TB drives I am using. I have swapped the 
drive out for a new one and am rebuilding right now. I am including the 
dump of the smartctl -x /dev/sdh below.


when i rebooted earlier mdadm kicked the device out so when I tried to 
--manage fail and --manage remove the drive it told me it did not exist.


I removed the old drive and installed a spanky new one.



I re formatted the drive with parted as follows (this is how I did my 
other drives - it is a 7 device raid):


#parted -a optimal

 >mklabel gpt

 >mkpart primary

 >>start 2048s

 >>end -1

 >set
 >>1

 >>raid

 >>on


I readded the newly formatted drive:

#mdadm --manage /dev/md0 --add /dev/sde1



When I check /proc/mdstat everthing seems to be going fine.


I did a smartctl -x on the other drives and they did not turn up this 
error. I will keep my eye on them though.


See below for the smartctl -x of the failed drive.


Thank-you again for your help.


- Justin


[root@BigBlue Desktop]# smartctl -x /dev/sdh
smartctl 5.43 2012-06-30 r3573 [x86_64-linux-2.6.32-431.3.1.el6.x86_64] 
(local build)
Copyright (C) 2002-12 by Bruce Allen, 
http://smartmontools.sourceforge.net

=== START OF INFORMATION SECTION ===
Model Family: Seagate Barracuda (SATA 3Gb/s, 4K Sectors)
Device Model: ST3000DM001-1CH166
Serial Number: Z1F3ZWAY
LU WWN Device Id: 5 000c50 0651b19cc
Firmware Version: CC27
User Capacity: 3,000,592,982,016 bytes [3.00 TB]
Sector Sizes: 512 bytes logical, 4096 bytes physical
Device is: In smartctl database [for details use: -P show]
ATA Version is: 8
ATA Standard is: ACS-2 (unknown minor revision code: 0x001f)
Local Time is: Mon Nov 17 17:58:16 2014 EST
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
AAM feature is: Unavailable
APM level is: 128 (minimum power consumption without standby)
Rd look-ahead is: Enabled
Write cache is: Enabled
ATA Security is: Disabled, frozen [SEC2]

=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED
See vendor-specific Attribute list for marginal Attributes.

General SMART Values:
Offline data collection status: (0x00) Offline data collection activity
was never started.
Auto Offline Data Collection: Disabled.
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: ( 584) seconds.
Offline data collection
capabilities: (0x73) SMART execute Offline immediate.
Auto Offline data collection on/off support.
Suspend Offline collection upon new
command.
No 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: ( 320) minutes.
Conveyance self-test routine
recommended polling time: ( 2) minutes.
SCT capabilities: (0x3085) SCT Status supported.

SMART Attributes Data Structure revision number: 10
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME FLAGS VALUE WORST THRESH FAIL RAW_VALUE
1 Raw_Read_Error_Rate POSR-- 114 099 006 - 73003456
3 Spin_Up_Time PO---- 094 094 000 - 0
4 Start_Stop_Count -O--CK 100 100 020 - 46
5 Reallocated_Sector_Ct PO--CK 100 100 010 - 0
7 Seek_Error_Rate POSR-- 044 043 030 - 2100251894876
9 Power_On_Hours -O--CK 092 092 000 - 7128
10 Spin_Retry_Count PO--C- 100 100 097 - 0
12 Power_Cycle_Count -O--CK 100 100 020 - 46
183 Runtime_Bad_Block -O--CK 099 099 000 - 1
184 End-to-End_Error -O--CK 094 094 099 NOW 6
187 Reported_Uncorrect -O--CK 100 100 000 - 0
188 Command_Timeout -O--CK 100 100 000 - 0
189 High_Fly_Writes -O-RCK 098 098 000 - 2
190 Airflow_Temperature_Cel -O---K 068 057 045 - 32 (Min/Max 31/33)
191 G-Sense_Error_Rate -O--CK 100 100 000 - 0
192 Power-Off_Retract_Count -O--CK 100 100 000 - 20
193 Load_Cycle_Count -O--CK 084 084 000 - 32594
194 Temperature_Celsius -O---K 032 043 000 - 32 (0 19 0 0 0)
197 Current_Pending_Sector -O--C- 100 100 000 - 0
198 Offline_Uncorrectable ----C- 100 100 000 - 0
199 UDMA_CRC_Error_Count -OSRCK 200 200 000 - 0
240 Head_Flying_Hours ------ 100 253 000 - 265527763141589
241 Total_LBAs_Written ------ 100 253 000 - 12406885927
242 Total_LBAs_Read ------ 100 253 000 - 141450480453
||||||_ K auto-keep
|||||__ C event count
||||___ R error rate
|||____ S speed/performance
||_____ O updated online
|______ P prefailure warning

General Purpose Log Directory Version 1
SMART Log Directory Version 1 [multi-sector log support]
GP/S Log at address 0x00 has 1 sectors [Log Directory]
SMART Log at address 0x01 has 1 sectors [Summary SMART error log]
SMART Log at address 0x02 has 5 sectors [Comprehensive SMART error log]
GP Log at address 0x03 has 5 sectors [Ext. Comprehensive SMART error 
log]
SMART Log at address 0x06 has 1 sectors [SMART self-test log]
GP Log at address 0x07 has 1 sectors [Extended self-test log]
SMART Log at address 0x09 has 1 sectors [Selective self-test log]
GP Log at address 0x10 has 1 sectors [NCQ Command Error log]
GP Log at address 0x11 has 1 sectors [SATA Phy Event Counters]
GP Log at address 0x21 has 1 sectors [Write stream error log]
GP Log at address 0x22 has 1 sectors [Read stream error log]
GP/S Log at address 0x80 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x81 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x82 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x83 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x84 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x85 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x86 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x87 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x88 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x89 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x8a has 16 sectors [Host vendor specific log]
GP/S Log at address 0x8b has 16 sectors [Host vendor specific log]
GP/S Log at address 0x8c has 16 sectors [Host vendor specific log]
GP/S Log at address 0x8d has 16 sectors [Host vendor specific log]
GP/S Log at address 0x8e has 16 sectors [Host vendor specific log]
GP/S Log at address 0x8f has 16 sectors [Host vendor specific log]
GP/S Log at address 0x90 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x91 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x92 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x93 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x94 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x95 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x96 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x97 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x98 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x99 has 16 sectors [Host vendor specific log]
GP/S Log at address 0x9a has 16 sectors [Host vendor specific log]
GP/S Log at address 0x9b has 16 sectors [Host vendor specific log]
GP/S Log at address 0x9c has 16 sectors [Host vendor specific log]
GP/S Log at address 0x9d has 16 sectors [Host vendor specific log]
GP/S Log at address 0x9e has 16 sectors [Host vendor specific log]
GP/S Log at address 0x9f has 16 sectors [Host vendor specific log]
GP/S Log at address 0xa1 has 20 sectors [Device vendor specific log]
GP Log at address 0xa2 has 4496 sectors [Device vendor specific log]
GP/S Log at address 0xa8 has 129 sectors [Device vendor specific log]
GP/S Log at address 0xa9 has 1 sectors [Device vendor specific log]
GP Log at address 0xab has 1 sectors [Device vendor specific log]
GP Log at address 0xb0 has 5176 sectors [Device vendor specific log]
GP Log at address 0xbe has 65535 sectors [Device vendor specific log]
GP Log at address 0xbf has 65535 sectors [Device vendor specific log]
GP/S Log at address 0xc0 has 1 sectors [Device vendor specific log]
GP/S Log at address 0xc1 has 10 sectors [Device vendor specific log]
GP/S Log at address 0xc4 has 5 sectors [Device vendor specific log]
GP/S Log at address 0xe0 has 1 sectors [SCT Command/Status]
GP/S Log at address 0xe1 has 1 sectors [SCT Data Transfer]

SMART Extended Comprehensive Error Log Version: 1 (5 sectors)
Device Error Count: 1
CR = Command Register
FEATR = Features Register
COUNT = Count (was: Sector Count) Register
LBA_48 = Upper bytes of LBA High/Mid/Low Registers ] ATA-8
LH = LBA High (was: Cylinder High) Register ] LBA
LM = LBA Mid (was: Cylinder Low) Register ] Register
LL = LBA Low (was: Sector Number) Register ]
DV = Device (was: Device/Head) Register
DC = Device Control Register
ER = Error register
ST = Status register
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 1 [0] occurred at disk power-on lifetime: 7093 hours (295 days + 
13 hours)
When the command that caused the error occurred, the device was active 
or idle.

After command completion occurred, registers were:
ER -- ST COUNT LBA_48 LH LM LL DV DC
-- -- -- == -- == == == -- -- -- -- --
04 -- 71 00 04 00 00 00 80 87 80 e0 00

Commands leading to the command that caused the error were:
CR FEATR COUNT LBA_48 LH LM LL DV DC Powered_Up_Time 
Command/Feature_Name
-- == -- == -- == == == -- -- -- -- -- --------------- 
--------------------
ea 00 00 00 00 00 00 00 00 00 00 a0 00 22d+15:53:02.331 FLUSH CACHE EXT
61 00 00 00 01 00 00 00 00 08 08 40 00 22d+15:53:02.330 WRITE FPDMA 
QUEUED
ea 00 00 00 00 00 00 00 00 00 00 a0 00 22d+15:53:02.330 FLUSH CACHE EXT
ea 00 00 00 00 00 00 00 00 00 00 a0 00 22d+15:52:40.493 FLUSH CACHE EXT
61 00 00 00 01 00 00 00 00 08 08 40 00 22d+15:52:40.492 WRITE FPDMA 
QUEUED

SMART Extended Self-test Log Version: 1 (1 sectors)
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error
# 1 Short offline Completed without error 00% 7120 -

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.

Warning: device does not support SCT Data Table command
Warning: device does not support SCT Error Recovery Control command
SATA Phy Event Counters (GP Log 0x11)
ID Size Value Description
0x000a 2 2 Device-to-host register FISes sent due to a COMRESET
0x0001 2 0 Command failed due to ICRC error
0x0003 2 0 R_ERR response for device-to-host data FIS
0x0004 2 0 R_ERR response for host-to-device data FIS
0x0006 2 0 R_ERR response for device-to-host non-data FIS
0x0007 2 0 R_ERR response for host-to-device non-data FIS









On Mon, Nov 17, 2014 at 12:19 PM, Chris Murphy <lists@colorremedies.com> 
wrote:


On Nov 16, 2014, at 6:34 PM, Justin Stephenson 
<justin@evensteveninc.com> wrote:

 > Thank-you, Chris. I appreciate your help with this.
 >
 > Backup are good. I'm a regular disk to disk to LTO guy. Here is what I 
have turned up:
 >
 > ================================
 > # smartctl -x /dev/sdh
 >
 > big long list of stuff.

Please post it.



 > I found the serial.
 >
 > I also tried smartctl -H /dev/sdh and received
 >
 > Overall-health self-assesment test restul: PASSED
 >
 > 184 End-to-End_Error {flag value worst thresh} Old_age FAILING_NOW_6

Cute, it’s failing but it’s overall health is passing. This is a great 
example of why the health self-assess is useless.


 >
 > I did not find anything for the serial in results from dmesg
 >
 > # smartctl -l scterc /dev/sdh
 >
 > Warning: device does not support SCT Commands

Interesting it supports a SMART IV attribut but doesn’t support SCT 
commands.


 >
 > # cat /sys/block/sdh/device/state
 >
 > Running
 >
 > # cat /sys/block/sdh/device/timeout
 >
 > 30

Since the drives you have don’t support SCT commands, you need to set 
the command timer to something much more than the default of 30, 
otherwise your array will not function correctly when it encounters bad 
sectors. In many cases the linux scsi command timer will reach 30 
seconds and reset the interface, before the typical consumer drive 
recovers (either returns data successfully or an error). This could be 
quite long, maybe 2 minutes. Future drives you buy should have 
configurable SCT ERC so the drive can be set to return a read error 
after something like 7 seconds, i.e. you want the drive to give up 
sooner, and by informing md of the problem sector range, the data is 
rebuilt from parity and written back to the bad sectors on the drive 
where the problem gets fixed.




 >
 > ================================
 >
 > Should I replace the drive or re add and resync?

Well I don’t know anything about attribute 184 End-to-End error, but 
based on the description in wikipedia it sounds disqualifying to me.

I personally would get the drive replaced no matter what: either under 
warranty, or if no warranty I’d get a new drive and test/play with this 
one offline and if it proves its worth then maybe it can be a spare down 
the road.

But you could also smartctl -x all the other drives and see what value 
they have for this attribute.

 >
 > I also went through and reseated all the SATA and power connections as 
I understand these can cause issues as well.




Chris Murphy



--

Even Steven Inc || Phone and Fax = 416-900-6069 || www.evensteveninc.com 
||
--------
Justin Stephenson
Creative Director/Motion Designer
416-900-6069
http://justinstephenson.com



------ Original Message ------
From: "Chris Murphy" <lists@colorremedies.com>
To: "Justin Stephenson" <justin@evensteveninc.com>
Cc: linux-raid@vger.kernel.org
Sent: 17/11/2014 12:19:26 PM
Subject: Re: Raid 6 Fail Event

>
>On Nov 16, 2014, at 6:34 PM, Justin Stephenson 
><justin@evensteveninc.com> wrote:
>
>>  Thank-you, Chris. I appreciate your help with this.
>>
>>  Backup are good. I'm a regular disk to disk to LTO guy. Here is what 
>>I have turned up:
>>
>>  ================================
>>  # smartctl -x /dev/sdh
>>
>>  big long list of stuff.
>
>Please post it.
>
>
>
>>  I found the serial.
>>
>>  I also tried smartctl -H /dev/sdh and received
>>
>>  Overall-health self-assesment test restul: PASSED
>>
>>  184 End-to-End_Error {flag value worst thresh} Old_age FAILING_NOW_6
>
>Cute, it’s failing but it’s overall health is passing. This is a great 
>example of why the health self-assess is useless.
>
>
>>
>>  I did not find anything for the serial in results from dmesg
>>
>>  # smartctl -l scterc /dev/sdh
>>
>>  Warning: device does not support SCT Commands
>
>Interesting it supports a SMART IV attribut but doesn’t support SCT 
>commands.
>
>
>>
>>  # cat /sys/block/sdh/device/state
>>
>>  Running
>>
>>  # cat /sys/block/sdh/device/timeout
>>
>>  30
>
>Since the drives you have don’t support SCT commands, you need to set 
>the command timer to something much more than the default of 30, 
>otherwise your array will not function correctly when it encounters bad 
>sectors. In many cases the linux scsi command timer will reach 30 
>seconds and reset the interface, before the typical consumer drive 
>recovers (either returns data successfully or an error). This could be 
>quite long, maybe 2 minutes. Future drives you buy should have 
>configurable SCT ERC so the drive can be set to return a read error 
>after something like 7 seconds, i.e. you want the drive to give up 
>sooner, and by informing md of the problem sector range, the data is 
>rebuilt from parity and written back to the bad sectors on the drive 
>where the problem gets fixed.
>
>
>
>
>>
>>  ================================
>>
>>  Should I replace the drive or re add and resync?
>
>Well I don’t know anything about attribute 184 End-to-End error, but 
>based on the description in wikipedia it sounds disqualifying to me.
>
>I personally would get the drive replaced no matter what: either under 
>warranty, or if no warranty I’d get a new drive and test/play with this 
>one offline and if it proves its worth then maybe it can be a spare 
>down the road.
>
>But you could also smartctl -x all the other drives and see what value 
>they have for this attribute.
>
>>
>>  I also went through and reseated all the SATA and power connections 
>>as I understand these can cause issues as well.
>
>
>
>
>Chris Murphy

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