hdparm - get/set hard disk parameters - version v6.6
Usage: hdparm [options] [device] ..
Options:
-a get/set fs readahead
-A set drive read-lookahead 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 IDE power mode status
-d get/set using_dma flag
--direct use O_DIRECT to bypass page cache for timings
-D enable/disable drive defect management
-E set cd-rom drive speed
-f flush buffer cache for device on exit
-g display drive geometry
-h display terse usage information
-i display drive identification
-I detailed/current information directly from drive
--Istdin read identify data from stdin as ASCII hex
--Istdout write identify data to stdout as ASCII hex
-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 acoustic management (0-254, 128: quiet, 254: fast) (EXPERIMENTAL)
-m get/set multiple sector count
-n get/set ignore-write-errors flag (0/1)
-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 tagged-queuing depth (if supported)
-r get/set device readonly flag (DANGEROUS to set)
-R register an IDE interface (DANGEROUS)
-S set standby (spindown) timeout
-t perform device read timings
-T perform cache read timings
-u get/set unmaskirq flag (0/1)
-U un-register an IDE interface (DANGEROUS)
-v defaults; same as -mcudkrag for IDE drives
-V display program version and exit immediately
-w perform device reset (DANGEROUS)
-W set drive write-caching flag (0/1) (DANGEROUS)
-x tristate device for hotswap (0/1) (DANGEROUS)
-X set IDE xfer mode (DANGEROUS)
-y put IDE drive in standby mode
-Y put IDE drive to sleep
-Z disable Seagate auto-powersaving mode
-z re-read partition table
--security-help display help for ATA security commands
