Tool to list drives that are unused by ZFS. Useful when you've just added a stack of new drives to a big ZFS system.

list-zfs-unused-drives.sh

#Get all drive info from ZDB, trim all path off the front and drop partition info from the back
used=$(zdb | grep -e ' path:' | sed -r "s/^.*(ata-.*)/\1/" | sed -r "s/(.*)-part1'|'/\1/" | sort)

#Get all ATA disks from the system
all=$(ls /dev/disk/by-id/ | grep -v part | grep -e ata- | sort)

#Compare both lists
unmatched=$(comm -13 <( echo "$used" ) <( echo "$all" ))

#Zpool status output to catch cache drives
zpool_status=$(zpool status)

#Print comparison output, highlight cache drices
while read -r line; do
        if grep -q $line <( echo "$zpool_status" ); then
                echo -e "\e[1;30m$line \e[1;33m**cache**\e[0m"
        else
                echo "$line"
        fi
done <<< "$unmatched"