A silly little script to potentially rebuild an fstab file based on the contents of mtab.

rebuild_fstab.sh

#!/usr/bin/env bash

while read line ; do
        if [ "$(echo $line | egrep '^\/dev\/sd')" != "" ] ; then
                dev="$(echo $line | awk '{ print $1 }')"
                id="$(blkid $dev | awk '{ print $2 }')"
                echo $line | sed -e "s|$dev|$id|"
        else
                echo $line
        fi
done < /etc/mtab