Howdy, I have a raid 5 where one drive reported this:
197 Current_Pending_Sector 0x0032 200 199 000 Old_age Always - 29
So I did this:
myth:~# echo check > /sys/block/md5/md/sync_action
[173947.749761] md: data-check of RAID array md5
(...)
[370316.769230] md: md5: data-check done.
My understanding was that it was supposed to read every block of every
drive, and if some blocks were unreadable, use parity to rewrite them on
some fresh backup blocks.
If a block returned garbage instead, md5 cannot fix this not knowing which
block is wrong, but I'm assuming the check would have failed with an error.
However after the check is over, I still have 29 Current_Pending_Sector on
that drive.
Since raid check succeeded, I'm going to assume that the sectors were
readable and did not return garbage, or I'd have gotten a parity mismatch
error.
Should then assume that either
1) the smart counter/logic is wrong?
2) the pending sectors started returning correct data again, so linux md has
no idea those blocks are "weak" and I have no easy way to forcibly remap
them.
3) the bad blocks did get remapped somehow, but the smart counter did not get
reset due to a firmware bug
4) other
After 2 days of testing with badblocks, it seems that it's #2, and I'm
not sure if there is anything raid check could have done (probably not)
Since raid check didn't do the job I was hoping for, I ran this instead:
myth:~# badblocks -nsv /dev/sdg
Checking for bad blocks in non-destructive read-write mode
>From block 0 to 3907018583
Checking for bad blocks (non-destructive read-write test)
Testing with random pattern: 57.87% done, 22:24:15 elapsed. (0/0/0 errors))
And this worked:
197 Current_Pending_Sector 0x0032 200 199 000 Old_age Always - 0
strangely, I also have:
5 Reallocated_Sector_Ct 0x0033 200 200 140 Pre-fail Always - 0
196 Reallocated_Event_Count 0x0032 200 200 000 Old_age Always - 0
I guess this means that my drive's auto reallocation logic is faulty and
that it will not re-allocate blocks that are weak, even after it was
able to read them.
Does that sound correct?
More drive details from before I ran badblocks (not an SMR drive):
Device Model: WDC WD40EFRX-68WT0N0
Serial Number: WD-WCC4E0642444
LU WWN Device Id: 5 0014ee 2b437e9a6
Firmware Version: 80.00A80
User Capacity: 4,000,787,030,016 bytes [4.00 TB]
1 Raw_Read_Error_Rate 0x002f 200 200 051 Pre-fail Always - 1617
3 Spin_Up_Time 0x0027 175 173 021 Pre-fail Always - 8250
4 Start_Stop_Count 0x0032 094 094 000 Old_age Always - 6773
5 Reallocated_Sector_Ct 0x0033 200 200 140 Pre-fail Always - 0
7 Seek_Error_Rate 0x002e 100 253 000 Old_age Always - 0
9 Power_On_Hours 0x0032 074 074 000 Old_age Always - 19092
10 Spin_Retry_Count 0x0032 100 100 000 Old_age Always - 0
11 Calibration_Retry_Count 0x0032 100 100 000 Old_age Always - 0
12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 158
192 Power-Off_Retract_Count 0x0032 200 200 000 Old_age Always - 91
193 Load_Cycle_Count 0x0032 182 182 000 Old_age Always - 54642
194 Temperature_Celsius 0x0022 121 103 000 Old_age Always - 31
196 Reallocated_Event_Count 0x0032 200 200 000 Old_age Always - 0
197 Current_Pending_Sector 0x0032 200 199 000 Old_age Always - 29
198 Offline_Uncorrectable 0x0030 200 200 000 Old_age Offline - 0
199 UDMA_CRC_Error_Count 0x0032 200 199 000 Old_age Always - 2
200 Multi_Zone_Error_Rate 0x0008 200 189 000 Old_age Offline - 0
SMART Self-test log structure revision number 1
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error
# 1 Short offline Completed without error 00% 19081 -
# 2 Short offline Completed without error 00% 19057 -
# 3 Short offline Completed without error 00% 19035 -
# 4 Short offline Completed without error 00% 18984 -
# 5 Extended offline Completed without error 00% 18974 -
Thanks,
Marc
--
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
Microsoft is to operating systems ....
.... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/
--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
