smartdがセクタ異常を検知

smartdから以下のようなメールが届いた。

Subject: SMART error (Health) detected on host: meadowsage.oheso.com
   
This email was generated by the smartd daemon running on:
   
   host name: meadowsage.oheso.com
  DNS domain: oheso.com
  NIS domain: (none)
   
The following warning/error was logged by the smartd daemon:
   
Device: /dev/hdb, FAILED SMART self-check. BACK UP DATA NOW!
   
For details see host's SYSLOG (default: /var/log/messages).
   
You can also use the smartctl utility for further investigation.
No additional email messages about this problem will be sent.

言われたとおり/var/log/messagesを確認してみる。

# cat /var/log/messages | grep smartd
Apr  9 04:32:22 meadowsage smartd[1727]: Device: /dev/hdb, 1 Currently unreadable (pending) sectors 
Apr  9 05:02:21 meadowsage smartd[1727]: Device: /dev/hdb, 1 Currently unreadable (pending) sectors 
Apr  9 05:32:21 meadowsage smartd[1727]: Device: /dev/hdb, 1 Currently unreadable (pending) sectors 
Apr  9 06:02:22 meadowsage smartd[1727]: Device: /dev/hdb, 1 Currently unreadable (pending) sectors 
Apr  9 06:32:21 meadowsage smartd[1727]: Device: /dev/hdb, 1 Currently unreadable (pending) sectors 
（※途中略）
Apr 12 15:02:21 meadowsage smartd[1727]: Device: /dev/hdb, 1 Currently unreadable (pending) sectors 
Apr 12 15:32:21 meadowsage smartd[1727]: Device: /dev/hdb, 1 Currently unreadable (pending) sectors 
Apr 12 16:02:22 meadowsage smartd[1727]: Device: /dev/hdb, 1 Currently unreadable (pending) sectors 
Apr 12 16:32:21 meadowsage smartd[1727]: Device: /dev/hdb, FAILED SMART self-check. BACK UP DATA NOW! 
Apr 12 16:32:21 meadowsage smartd[1727]: Sending warning via mail to root@oheso.com ... 
Apr 12 16:32:22 meadowsage smartd[1727]: Warning via mail to root@oheso.com: successful 
Apr 12 16:32:22 meadowsage smartd[1727]: Device: /dev/hdb, 1 Currently unreadable (pending) sectors 
Apr 12 17:02:21 meadowsage smartd[1727]: Device: /dev/hdb, FAILED SMART self-check. BACK UP DATA NOW! 
Apr 12 17:02:21 meadowsage smartd[1727]: Device: /dev/hdb, 1 Currently unreadable (pending) sectors 
Apr 12 17:32:21 meadowsage smartd[1727]: Device: /dev/hdb, FAILED SMART self-check. BACK UP DATA NOW! 
Apr 12 17:32:22 meadowsage smartd[1727]: Device: /dev/hdb, 1 Currently unreadable (pending) sectors 
Apr 12 18:02:21 meadowsage smartd[1727]: Device: /dev/hdb, FAILED SMART self-check. BACK UP DATA NOW! 
Apr 12 18:02:21 meadowsage smartd[1727]: Device: /dev/hdb, 1 Currently unreadable (pending) sectors 

/dev/hdbに読めないセクタがあると言ってるようだが、たった1つというのが難儀である。ちなみに、RAID構成自体には何の問題もない。

# cat /proc/mdstat
Personalities : [raid1] 
md1 : active raid1 hdb2[1] hda2[0]
      38089984 blocks [2/2] [UU]
      
md0 : active raid1 hdb1[1] hda1[0]
      104192 blocks [2/2] [UU]
      
unused devices: <none>

念のため、S.M.A.R.T.への対応状況を調べてみたが、こちらも異常なし。

# smartctl -i /dev/hdb
smartctl version 5.33 [i386-redhat-linux-gnu] Copyright (C) 2002-4 Bruce Allen
Home page is http://smartmontools.sourceforge.net/
   
=== START OF INFORMATION SECTION ===
Device Model:     MAXTOR 6L040J2
Serial Number:    662221222518
Firmware Version: A93.0500
User Capacity:    40,027,029,504 bytes
Device is:        In smartctl database [for details use: -P show]
ATA Version is:   5
ATA Standard is:  ATA/ATAPI-5 T13 1321D revision 1
Local Time is:    Wed Apr 12 17:54:54 2006 JST
SMART support is: Available - device has SMART capability.
SMART support is: Enabled

う〜ん、たった1つのセクタ不良だけでHDD取り替えるのもなぁ……。