Centos 7 查看硬盘通电时间 smartmontools

查看硬盘的通电时间，可以安装Smartctl (意思是：Self-Monitoring, Analysis and Reporting Technology)

Smartcl在CentOS下的安装步骤:

登录你的服务器
用yum安装Smartcl，具体命令
```
yum install smartmontools
```
查看
```
smartctl -A /dev/sda
```

下面截图是一台服务器的通电时间，只有233个小时，挺新的硬盘。

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       -       0
  2 Throughput_Performance  0x0004   100   100   000    Old_age   Offline      -       0
  3 Spin_Up_Time            0x0007   131   131   033    Pre-fail  Always       -       2
  4 Start_Stop_Count        0x0012   100   100   000    Old_age   Always       -       11
  5 Reallocated_Sector_Ct   0x0033   100   100   005    Pre-fail  Always       -       0
  7 Seek_Error_Rate         0x000a   100   100   000    Old_age   Always       -       0
  8 Seek_Time_Performance   0x0004   100   100   000    Old_age   Offline      -       0
  9 Power_On_Hours          0x0012   100   100   000    Old_age   Always       -       233
 10 Spin_Retry_Count        0x0012   100   100   000    Old_age   Always       -       0
 12 Power_Cycle_Count       0x0032   100   100   000    Old_age   Always       -       11
191 G-Sense_Error_Rate      0x000a   100   100   000    Old_age   Always       -       0
192 Power-Off_Retract_Count 0x0032   100   100   000    Old_age   Always       -       3
193 Load_Cycle_Count        0x0012   099   099   000    Old_age   Always       -       12775
194 Temperature_Celsius     0x0002   206   206   000    Old_age   Always       -       29 (Min/Max 19/35)
196 Reallocated_Event_Count 0x0032   100   100   000    Old_age   Always       -       0
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
223 Load_Retry_Count        0x000a   100   100   000    Old_age   Always       -       0
240 Head_Flying_Hours       0x0032   100   100   000    Old_age   Always       -       13
241 Total_LBAs_Written      0x0032   100   100   000    Old_age   Always       -       160550202
242 Total_LBAs_Read         0x0032   100   100   000    Old_age   Always       -       3935552
254 Free_Fall_Sensor        0x0032   100   100   000    Old_age   Always       -       0