Dobrica Pavlinušić's random unstructured stuff

Bad block HOWTO for smartmontools: Revision 2

My transcript for fixing error based on "original documentation"<http://smartmontools.sourceforge.net/badblockhowto.html>

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root@t42:~# smartctl -l selftest /dev/hda
smartctl version 5.38 [i686-pc-linux-gnu] Copyright (C) 2002-8 Bruce Allen
Home page is http://smartmontools.sourceforge.net/

=== START OF READ SMART DATA SECTION ===
SMART Self-test log structure revision number 1
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error
# 1 Extended offline Completed: read failure 50% 1863 48784734
# 2 Extended offline Completed: read failure 50% 1719 48784734
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*sic* we have an error at `48784734`

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root@t42:~# smartctl -A /dev/hda
smartctl version 5.38 [i686-pc-linux-gnu] Copyright (C) 2002-8 Bruce Allen
Home page is http://smartmontools.sourceforge.net/

=== START OF READ SMART DATA SECTION ===
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 0x000b 100 100 062 Pre-fail Always - 65536
2 Throughput_Performance 0x0005 100 100 040 Pre-fail Offline - 3662
3 Spin_Up_Time 0x0007 250 250 033 Pre-fail Always - 1
4 Start_Stop_Count 0x0012 100 100 000 Old_age Always - 1520
5 Reallocated_Sector_Ct 0x0033 100 100 005 Pre-fail Always - 0
7 Seek_Error_Rate 0x000b 100 100 067 Pre-fail Always - 0
8 Seek_Time_Performance 0x0005 100 100 040 Pre-fail Offline - 0
9 Power_On_Hours 0x0012 096 096 000 Old_age Always - 1866
10 Spin_Retry_Count 0x0013 100 100 060 Pre-fail Always - 0
12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 1319
191 G-Sense_Error_Rate 0x000a 100 100 000 Old_age Always - 1
192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 1703983
193 Load_Cycle_Count 0x0012 095 095 000 Old_age Always - 56800
194 Temperature_Celsius 0x0002 171 171 000 Old_age Always - 32 (Lifetime Min/Max 14/42)
196 Reallocated_Event_Count 0x0032 100 100 000 Old_age Always - 5
197 Current_Pending_Sector 0x0022 100 100 000 Old_age Always - 1
198 Offline_Uncorrectable 0x0008 100 100 000 Old_age Offline - 0
199 UDMA_CRC_Error_Count 0x000a 200 200 000 Old_age Always - 0
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And we do have `Current_Pending_Sector`

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root@t42:~# fdisk -lu /dev/hda

Disk /dev/hda: 40.0 GB, 40007761920 bytes
255 heads, 63 sectors/track, 4864 cylinders, total 78140160 sectors
Units = sectors of 1 * 512 = 512 bytes
Disk identifier: 0xcccdcccd

Device Boot Start End Blocks Id System
/dev/hda1 * 63 75119939 37559938+ 83 Linux
/dev/hda2 75119940 78140159 1510110 5 Extended
/dev/hda5 75120003 78140159 1510078+ 82 Linux swap / Solaris
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sector is part of `/dev/hda1`

let's find it:

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root@t42:~# tune2fs -l /dev/hda1 | grep Block
Block count: 9389984
Block size: 4096
Blocks per group: 32768

root@t42:~# bc
( ( 48784734 - 63 ) * 512 ) / 4096
6098083

root@t42:~# debugfs /dev/hda1
debugfs 1.41.3 (12-Oct-2008)
debugfs: icheck 6098083
Block Inode number
6098083 <block not found>
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so no files landed on it yet. so let's just relocate it:

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root@t42:~# dd if=/dev/zero of=/dev/hda1 bs=4096 count=1 seek=6098083
1+0 records in
1+0 records out
4096 bytes (4.1 kB) copied, 6.0343e-05 s, 67.9 MB/s
root@t42:~# sync

root@t42:~# smartctl -A /dev/hda
smartctl version 5.38 [i686-pc-linux-gnu] Copyright (C) 2002-8 Bruce Allen
Home page is http://smartmontools.sourceforge.net/

=== START OF READ SMART DATA SECTION ===
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 0x000b 100 100 062 Pre-fail Always - 1
2 Throughput_Performance 0x0005 100 100 040 Pre-fail Offline - 3662
3 Spin_Up_Time 0x0007 250 250 033 Pre-fail Always - 1
4 Start_Stop_Count 0x0012 100 100 000 Old_age Always - 1520
5 Reallocated_Sector_Ct 0x0033 100 100 005 Pre-fail Always - 0
7 Seek_Error_Rate 0x000b 100 100 067 Pre-fail Always - 0
8 Seek_Time_Performance 0x0005 100 100 040 Pre-fail Offline - 0
9 Power_On_Hours 0x0012 096 096 000 Old_age Always - 1866
10 Spin_Retry_Count 0x0013 100 100 060 Pre-fail Always - 0
12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 1319
191 G-Sense_Error_Rate 0x000a 100 100 000 Old_age Always - 1
192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 1703983
193 Load_Cycle_Count 0x0012 095 095 000 Old_age Always - 56800
194 Temperature_Celsius 0x0002 157 157 000 Old_age Always - 35 (Lifetime Min/Max 14/42)
196 Reallocated_Event_Count 0x0032 100 100 000 Old_age Always - 6
197 Current_Pending_Sector 0x0022 100 100 000 Old_age Always - 0
198 Offline_Uncorrectable 0x0008 100 100 000 Old_age Offline - 0
199 UDMA_CRC_Error_Count 0x000a 200 200 000 Old_age Always - 0
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Let's run test again

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root@t42:~# smartctl -t long /dev/hda
smartctl version 5.38 [i686-pc-linux-gnu] Copyright (C) 2002-8 Bruce Allen
Home page is http://smartmontools.sourceforge.net/

=== START OF OFFLINE IMMEDIATE AND SELF-TEST SECTION ===
Sending command: "Execute SMART Extended self-test routine immediately in off-line mode".
Drive command "Execute SMART Extended self-test routine immediately in off-line mode" successful.
Testing has begun.
Please wait 29 minutes for test to complete.
Test will complete after Tue Jan 27 14:07:03 2009

Use smartctl -X to abort test.
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