URGENT: Why does my system send me this email? Harddisk Down?

[congkai]

People, urgent help, my system send me 3 emails yesterday. i dont know what does the email means. can someone help me to see?

Email1

This is an automatically generated mail message from mdadm
running on ns1.alphaelite.net

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

It could be related to component device /dev/sdb1.

Faithfully yours, etc.

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

Personalities : [raid1] 
md0 : active raid1 sdb1[1](F) sda1[0]
      486287424 blocks [2/1] [U_]

Email2
SMART error (FailedHealthCheck) detected

This email was generated by the smartd daemon running on:

   host name: ns1.123e.net
  DNS domain: 123e.net
  NIS domain: (none)

The following warning/error was logged by the smartd daemon:

Device: /dev/sdb, not capable of SMART self-check

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.

Email3
SMART error (FailedReadSmartData) detected

This email was generated by the smartd daemon running on:

   host name: ns1.123e.net
  DNS domain: 123e.net
  NIS domain: (none)

The following warning/error was logged by the smartd daemon:

Device: /dev/sdb, failed to read SMART Attribute Data

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.

 

[floyd]

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

It could be related to component device /dev/sdb1.

Device: /dev/sdb, not capable of SMART self-check

Device: /dev/sdb, failed to read SMART Attribute Data

The emails seem pretty clear to me. /dev/sdb is failing. You need to replace it.

 

[nobaloney]

It's almost always worth trying to rebuild the RAID first.

Jeff