1. 前言

最近搞了个nas机箱，里面可以装4块机箱硬盘，J1900u, 虽然有黑群晖系统，但是总感觉不够灵活（对于raid 硬盘模式我是完全用不上，读写速度没需求，数据安全性也没需求，最主要是要灵活），所有最终还是装了ubuntu server。
那么对于机械硬盘，硬盘休眠是我需要研究的。虽然是垃圾硬盘，软件层面上能延长寿命还是尽量延长一下吧。

2. 工具

sudo apt install hdparm

hdparm -h
hdparm - get/set hard disk parameters - version v9.60, by Mark Lord.Usage:  hdparm  [options] [device ...]Options:-a   Get/set fs readahead-A   Get/set the drive look-ahead flag (0/1)-b   Get/set bus state (0 == off, 1 == on, 2 == tristate)-B   Set Advanced Power Management setting (1-255)-c   Get/set IDE 32-bit IO setting-C   Check drive power mode status-d   Get/set using_dma flag-D   Enable/disable drive defect management-E   Set cd/dvd drive speed-f   Flush buffer cache for device on exit-F   Flush drive write cache-g   Display drive geometry-h   Display terse usage information-H   Read temperature from drive (Hitachi only)-i   Display drive identification-I   Detailed/current information directly from drive-J   Get/set Western DIgital "Idle3" timeout for a WDC "Green" drive (DANGEROUS)-k   Get/set keep_settings_over_reset flag (0/1)-K   Set drive keep_features_over_reset flag (0/1)-L   Set drive doorlock (0/1) (removable harddisks only)-m   Get/set multiple sector count-M   Get/set acoustic management (0-254, 128: quiet, 254: fast)-n   Get/set ignore-write-errors flag (0/1)-N   Get/set max visible number of sectors (HPA) (VERY DANGEROUS)-p   Set PIO mode on IDE interface chipset (0,1,2,3,4,...)-P   Set drive prefetch count-q   Change next setting quietly-Q   Get/set DMA queue_depth (if supported)-r   Get/set device readonly flag (DANGEROUS to set)-R   Get/set device write-read-verify flag-s   Set power-up in standby flag (0/1) (DANGEROUS)-S   Set standby (spindown) timeout-t   Perform device read timings-T   Perform cache read timings-u   Get/set unmaskirq flag (0/1)-U   Obsolete-v   Use defaults; same as -acdgkmur for IDE drives-V   Display program version and exit immediately-w   Perform device reset (DANGEROUS)-W   Get/set drive write-caching flag (0/1)-x   Obsolete-X   Set IDE xfer mode (DANGEROUS)-y   Put drive in standby mode-Y   Put drive to sleep-z   Re-read partition table-Z   Disable Seagate auto-powersaving mode--dco-freeze      Freeze/lock current device configuration until next power cycle--dco-identify    Read/dump device configuration identify data--dco-restore     Reset device configuration back to factory defaults--dco-setmax      Use DCO to set maximum addressable sectors--direct          Use O_DIRECT to bypass page cache for timings--drq-hsm-error   Crash system with a "stuck DRQ" error (VERY DANGEROUS)--fallocate       Create a file without writing data to disk--fibmap          Show device extents (and fragmentation) for a file--fwdownload            Download firmware file to drive (EXTREMELY DANGEROUS)--fwdownload-mode3      Download firmware using min-size segments (EXTREMELY DANGEROUS)--fwdownload-mode3-max  Download firmware using max-size segments (EXTREMELY DANGEROUS)--fwdownload-mode7      Download firmware using a single segment (EXTREMELY DANGEROUS)--fwdownload-modee      Download firmware using mode E (min-size segments) (EXTREMELY DANGEROUS)--fwdownload-modee-max  Download firmware using mode E (max-size segments) (EXTREMELY DANGEROUS)--idle-immediate  Idle drive immediately--idle-unload     Idle immediately and unload heads--Iraw filename   Write raw binary identify data to the specfied file--Istdin          Read identify data from stdin as ASCII hex--Istdout         Write identify data to stdout as ASCII hex--make-bad-sector Deliberately corrupt a sector directly on the media (VERY DANGEROUS)--offset          use with -t, to begin timings at given offset (in GiB) from start of drive--prefer-ata12    Use 12-byte (instead of 16-byte) SAT commands when possible--read-sector     Read and dump (in hex) a sector directly from the media--repair-sector   Alias for the --write-sector option (VERY DANGEROUS)--sanitize-antifreeze-lock  Block sanitize-freeze-lock command until next power cycle--sanitize-block-erase      Start block erase operation--sanitize-crypto-scramble  Change the internal encryption keys that used for used data--sanitize-freeze-lock      Lock drive's sanitize features until next power cycle--sanitize-overwrite  PATTERN  Overwrite the internal media with constant PATTERN--sanitize-status           Show sanitize status information--security-help             Display help for ATA security commands--set-sector-size           Change logical sector size of drive--trim-sector-ranges        Tell SSD firmware to discard unneeded data sectors: lba:count ..--trim-sector-ranges-stdin  Same as above, but reads lba:count pairs from stdin--verbose                   Display extra diagnostics from some commands--write-sector              Repair/overwrite a (possibly bad) sector directly on the media (VERY DANGEROUS)

3. 使用方式

常用的几个参数：

sudo hdparm -y /dev/sdc  #进入待机模式
sudo hdparm -C /dev/sdc  #查询当前硬盘状态
sudo hdparm -S 1 /dev/sdc #5s后进入待机，实际乘以5倍

因为我的机械硬盘不支持APM 所有没做过多研究， standby mode已经可以满足我需求了。

修改配置文件：
/etc/hdparm.conf

/dev/sdb {force_spindown_time = 60
}/dev/sdc {force_spindown_time = 60
}

这里配置要注意花括号后面的空格，另外设备支持uuid描述方式，可以参考example

上面的配置相当于 300s (5分钟) 无操作，硬盘自动进入 standy mode

立刻生效配置文件：

/usr/lib/pm-utils/power.d/95hdparm-apm resume

每次电脑重启后 会自动生效配置文件中的配置

4. 解决一个问题

在实际使用过长中，我发现如果在硬盘 standby mode状态下, 连接ssh 会使硬盘 变为active, 这不是我想要的。

sudo chmod -x /etc/update-motd.d/98-fsck-at-reboot

可以解决， 具体和ubuntu 的motd有关，没细研究，可以参考：链接