Remove multipath LUN from Linux without reboot

remove_lun.sh

#!/bin/bash

# Script for removing multipathed LUNs from Linux hosts without a reboot
# 2022 Ilmar Kerm

if [ $# -eq 0 ]; then
  echo "Usage: remove_lun.sh lunid"
  echo "Example: remove_lun.sh 36005076810818379800000000000000c"
  exit 1
fi

# Find DM device name
lunid="$1"
dmdev=$(multipath -ll "$lunid" | grep "$lunid" | cut -d' ' -f 2)
if [[ -z "$dmdev" || "${dmdev:0:3}" != "dm-" ]]; then
  echo "Did not find DM device"
  exit 1
fi

echo "LUN: $lunid"
echo "DM device: $dmdev"

# Find slave devices
if [ ! -d "/sys/block/${dmdev}/slaves" ]; then
  echo "Should not be here. Did not find directory /sys/block/${dmdev}/slaves"
  exit 1
fi

# Remove slave devices
for f in $(ls -1 "/sys/block/${dmdev}/slaves" ); do
  echo -n "Removing slave: $f"
  echo 1 > /sys/block/$f/device/delete
  echo " done"
done

# Remove multipath device
sleep 5s
multipath -f "$lunid"