Scaning for SCSI/libata hard disks

Scanning for disks

To get host adapters to scan for new devices, 'echo "- - -"' to the scan file. The following command will cause all host adapters to scan their buses:

# for A in /sys/class/scsi_host/host[0-9]*/scan ; do cat ${A%/scan}/proc_name ; echo "- - -" > $A ; done

Note: If the driver for the host adapter doesn't support warm-swap, then the echo command will fail with the message 'write error: Operation not supported'. e.g. Linux 2.6.22 sata_mv driver.

Manually deleting disks

This script allows the 'warm' removal for SCSI disk by specifying their device name. Examples

scsi-delete /dev/sd[a-e]
scsi-delete /dev/sda

The '-d' dry-run option shows which SCSI nodes would be deleted.

scsi-delete

#!/bin/sh


set -e
#
# Parse switches
#
while [ "$1" != "${1##-}" ] ; do # loop over options
    case $1 in
        -v)
                VERBOSE=yes
        ;;

        -d)
                DRYRUN=yes
        ;;

        *)
                echo "Warning: Unknown option $1"
                exit 10;
        ;;

    esac
    shift
done


if [ $# -eq 0 ] ; then
  echo "Usage: $0 -v device ..."

  echo
  echo "Known SCSI devices are:"
  for DEVICE in /sys/bus/scsi/devices/* ; do
    NAME=`ls $DEVICE | grep '^block\:' | sed -e 's/block://'`
    echo "  ${NAME}"
  done
  exit 1
fi


while [ "$#" -gt 0 ] ; do # loop over options

  # Just use the filename part of the device path
  DEVICE_NAME="${1##*/}"
  [ -n "$VERBOSE" ] && echo "Attempting to delete SCSI device with $1 ($DEVICE_NAME)"

  # enumerate all SCSI devices
  for DEVICE in /sys/bus/scsi/devices/* ; do

    # get the block device name for the SCSI device (assumes one name only)
    NAME=`ls $DEVICE | grep '^block\:' | sed -e 's/block://'`
    [ -n "$VERBOSE" ] && echo "  Checking SCSI device $DEVICE ($NAME)"

    # Check if the SCSI block device name matches the command line arg
    if [ "$DEVICE_NAME" = "$NAME" ] ; then
      [ -n "$VERBOSE" ] && echo "  Checking SCSI device ${DEVICE} ($NAME)"

      # Delete the SCSI device
      echo "Deleting device $DEVICE (${NAME})"
      if [ -n "$DRYRUN" ] ; then
         echo "  Dry run - device $DEVICE NOT deleted"
      else
         echo 1 > $DEVICE/delete
      fi
    fi
  done

  shift
done