Re: IDE and hot-swap disk caddies

Mark Lord (
Thu, 28 Mar 2002 13:10:55 -0500

hdparm - get/set hard disk parameters - version v4.6

Usage: hdparm [options] [device] ..

-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 get 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
-D enable/disable drive defect-mgmt
-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
-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
-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
-r get/set 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 default; same as -acdgkmnru (-gr for SCSI, -adgr for XT)
-V display program version and exit immediately
-w perform device reset (DANGEROUS)
-W set drive write-caching flag (0/1) (DANGEROUS)
-x perform device for hotswap flag (0/1) (DANGEROUS)
-X set IDE xfer mode (DANGEROUS)
-y put IDE drive in standby mode
-Y put IDE drive to sleep

Mark Lord
Real-Time Remedies Inc.
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