Linux: How to delete a disk or LUN reference from /dev

In AIX, there is rmdev command to remove a disk/LUN from /dev directory i.e to make the disk/LUN unavailable to the whole OS before physically removing it.

But in Linux, there‘s no specific command to the same. Here‘s how you will actually do it:

Make sure that the disk is not being used by the application, does not contain a mounted file system or an active volume group.

1. Take the disk offline:

cd /sys/block/sdb/device

echo “offline” >state

2. Delete from /dev

echo 1 >delete

You can make your own script with the name rmdev ;)

#!/bin/ksh

dev=$1

[[ ! -d "$dev" ]] && echo "$dev does not exist" && exit 1

echo "offline" >/sys/block/"$dev"/device/state

echo 1 >/sys/block/"$dev"/device/delete