[SOLVED] Bad Sectors Found.

[Sethanath]

Hi,

I came from Windows XP to Fedora 17 for about three days. Previously, I would run chdisk all the times with my drive when I was using XP. Now, I formatted that computer completely, and installed Fedora 17. I also learned about SMART Start Self-test today. I executed such Start Self-test (Extended), and I found 2 bad sectors

I heard that there are Hard and soft bad sectors -> http://www.auslogics.com/en/articles/bad-sector/

1. Does this mean Fedora SMART Self-test is more efficient than Windows chdisk since I found bad sectors today, but none previously.
2. Now, I am also hoping that my two bad sectors are soft ones. How am i going to fix them in Fedora?

Your helps are greatly appreciated.

Originally Posted by Sethanath

Hi,

I came from Windows XP to Fedora 17 for about three days. Previously, I would run chdisk all the times with my drive when I was using XP. Now, I formatted that computer completely, and installed Fedora 17. I also learned about SMART Start Self-test today. I executed such Start Self-test (Extended), and I found 2 bad sectors

I heard that there are Hard and soft bad sectors -> http://www.auslogics.com/en/articles/bad-sector/

1. Does this mean Fedora SMART Self-test is more efficient than Windows chdisk since I found bad sectors today, but none previously.
2. Now, I am also hoping that my two bad sectors are soft ones. How am i going to fix them in Fedora?

Your helps are greatly appreciated.

The link you posted is complete rubbish, they just want to sell you some ****** software which wont help
You have two choices IMO.

1. run something like seatools and mark the blocks as bad.

http://www.seagate.com/support/downloads/seatools/

2. buy a new harddrive.


Option 2 is the best IMO.

[Sethanath]

May I ask how big is two sectors? Also, the link you gave me is for Windows and Dos.

Thanks.

---------- Post added at 08:24 AM ---------- Previous post was at 08:24 AM ----------

Also, can't we just do it from Fedora?

Originally Posted by Sethanath

May I ask how big is two sectors? Also, the link you gave me is for Windows and Dos.

Thanks.

---------- Post added at 08:24 AM ---------- Previous post was at 08:24 AM ----------

Also, can't we just do it from Fedora?

I don't know about the linux options for this.
IMO the dos cd image is a good choice

http://www.seagate.com/support/inter...ls-dos-master/

[DBelton]

2 sectors is 1024 bytes. (on a 512 byte sector drive) and 8192 bytes on some of the newer 4k sector drives.

However, if you are looking at the SMART information on the drive, if you have 2 sectors shown as reallocated, then there is nothing more you need to do. (and really nothing more that you can do)

Windows chkdsk doesn't show you what is in the SMART table on the drive, but if it finds a bad sector when checking, it is supposed to reallocate it. So unless you checked the SMART information before you installed Fedora, it's possible that those bad sectors may have been there for quite a long time.

It's just that Fedora (with Gnome disk utility) will pop up a warning if there are any reallocated sectors, whereas Windows doesn't.

Now if they are shown in your SMART information as Pending reallocations, then there is possibility that you can have them marked as good (or bad) depending upon what condition your drive is in. A Pending sector reallocation will be marked as good if there is a successful write to the sector.

Pending reallocations can be reset. Reallocated sectors can not be reset. They will be marked as bad for the life of the drive. Even if the sector really isn't bad, there is no way to go in and reset the information in the drives SMART table.

[Sethanath]

Wow. Thank you. Yes, they are shown as reallocated in some way. I also believe I saw them as pending reallocation some how.

Now, how do I know what condition my drive is in?
How do I reset them if they are in pending reallocations?
How do I check if they are reallocated sectors?

Thank you.

[DBelton]

run smartctl on your drive to list the values in the SMART table.

su -
(root password)

smartctl --all /dev/sda

You should get all kinds of information, like so:

[root@tower20 ~]# smartctl --all /dev/sda
smartctl 5.43 2012-06-30 r3573 [x86_64-linux-3.5.0-2.fc17.x86_64] (local build)
Copyright (C) 2002-12 by Bruce Allen, http://smartmontools.sourceforge.net

=== START OF INFORMATION SECTION ===
Model Family:     Western Digital Caviar Black
Device Model:     WDC WD2001FASS-00W2B0
Serial Number:    WD-WMAY00556503
LU WWN Device Id: 5 0014ee 0027b8ca5
Firmware Version: 05.01D05
User Capacity:    2,000,398,934,016 bytes [2.00 TB]
Sector Size:      512 bytes logical/physical
Device is:        In smartctl database [for details use: -P show]
ATA Version is:   8
ATA Standard is:  Exact ATA specification draft version not indicated
Local Time is:    Mon Aug  6 14:11:36 2012 CDT
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:  (0x84)	Offline data collection activity
					was suspended by an interrupting command from host.
					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: 		(29160) 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: 	 (   2) minutes.
Extended self-test routine
recommended polling time: 	 ( 297) minutes.
Conveyance self-test routine
recommended polling time: 	 (   5) minutes.
SCT capabilities: 	       (0x3037)	SCT Status supported.
					SCT Feature Control supported.
					SCT Data Table supported.

SMART Attributes Data Structure revision number: 16
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
  1 Raw_Read_Error_Rate     0x002f   200   200   051    Pre-fail  Always       -       0
  3 Spin_Up_Time            0x0027   176   166   021    Pre-fail  Always       -       13166
  4 Start_Stop_Count        0x0032   100   100   000    Old_age   Always       -       455
  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   088   088   000    Old_age   Always       -       9347
 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       -       448
192 Power-Off_Retract_Count 0x0032   200   200   000    Old_age   Always       -       181
193 Load_Cycle_Count        0x0032   184   184   000    Old_age   Always       -       48361
194 Temperature_Celsius     0x0022   111   099   000    Old_age   Always       -       41
196 Reallocated_Event_Count 0x0032   200   200   000    Old_age   Always       -       0
197 Current_Pending_Sector  0x0032   200   200   000    Old_age   Always       -       0
198 Offline_Uncorrectable   0x0030   200   200   000    Old_age   Offline      -       0
199 UDMA_CRC_Error_Count    0x0032   200   200   000    Old_age   Always       -       0
200 Multi_Zone_Error_Rate   0x0008   200   200   000    Old_age   Offline      -       1

SMART Error Log Version: 1
No Errors Logged

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%         0         -

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.

The line:

5 Reallocated_Sector_Ct 0x0033 200 200 140 Pre-fail Always - 0

Tells you how many sectors have been reallocated. There are quite a few spare sectors on a drive, so you still have full capacity unless you have a ton of errors. (look in the last column for the value - labelled Raw_Value)

The Pending allocations are also shown on the line:

197 Current_Pending_Sector 0x0032 200 200 000 Old_age Always - 0

Same thing. Look at the Raw_Value (last column) and it will tell you how many pending reallocations there are.

And like I said above. Pending reallocations are temporary. If you have a good write to the sector, it should get reset. If it gets a bad write to the sector, then it will reallocate it.

[Penguinclaw]

Thanks DBelton and sethanath for the heads up on bad sectors as I have a couple of drives that have these and I will now be able to test them with SMART I am a little confused though: if bad sectors are found, at what point should you replace said drive? Or does the SMART system provide protection from complete failure? I do keep backups of important data.

[Sethanath]

Here is mine.

[Sethanath]

Thanks so much.

[DBelton]

Originally Posted by Penguinclaw

Thanks DBelton and sethanath for the heads up on bad sectors as I have a couple of drives that have these and I will now be able to test them with SMART I am a little confused though: if bad sectors are found, at what point should you replace said drive? Or does the SMART system provide protection from complete failure? I do keep backups of important data.

Every drive has a number of spare sectors that it uses to remap bad sectors to. If you just have one or two bad sectors, and don't get any more, then the drive can still run for years without a problem. What you really need to keep an eye out for is if a drive suddenly starts reallocating bad sectors pretty quickly. That can be an indication of drive failure.

And, no, SMART doesn't provide any protection from complete failure, however, it does serve to warn you in a lot of cases of pending failure. You might have an opportunity to get your valuable data off the drive before it does fail.

But, if all you have is a few bad sectors, and not getting any more, then I wouldn't worry too much about it.


Sethanath:

Yours shows 1 bad (reallocated) sector and 1 Pending. The one that has already been reallocated, there isn't much that can be done about it. It's been reallocated with a good sector from the spares. The Pending sector may or may not be bad. You probably won't know until you try to write that sector again.

[Sethanath]

I got it now.

[Penguinclaw]

Originally Posted by DBelton

Every drive has a number of spare sectors that it uses to remap bad sectors to. If you just have one or two bad sectors, and don't get any more, then the drive can still run for years without a problem. What you really need to keep an eye out for is if a drive suddenly starts reallocating bad sectors pretty quickly. That can be an indication of drive failure.

And, no, SMART doesn't provide any protection from complete failure, however, it does serve to warn you in a lot of cases of pending failure. You might have an opportunity to get your valuable data off the drive before it does fail.

But, if all you have is a few bad sectors, and not getting any more, then I wouldn't worry too much about it.

Thanks, thats cleared that up for me