#!/bin/bash
# Script per rinominare i volumes group su VM Debian
# Autore: Mattia Tadini
# Nome File: rename-vg.sh
# Revisione: 1.0

# Must be run with root permissions
# sudo will be sufficient
if [ "$(id -u)" -ne 0 ]; then
   echo "This script must be run as root" 1>&2
   exit 1
fi

# Ask for new hostname $newhost
echo Set a New Volume Group  Name:
read newhostname -p "Enter new hostname: "
#oldhostname=$(cat /etc/hostname)

echo Changing LVM names
# ${var//-} syntax removes all dashes from the name simplifying the
# requirement to use a double-dash in some places to escape the dash
newvg=${newhostname//-}

# Find the volume group that root is in
vg=$(lvdisplay -C | awk '$1=="root" {print $2}')
echo "old vg name: " $vg
echo "new vg name: " $newvg
if [[ ${vg} == *"-"* ]]; then
    # has dashes in current name
    vgrename ${vg} ${newhostname//-}
    vg=${vg//-/--}
    sed -i "s/${vg}/${newvg}/g" /etc/fstab
    sed -i "s/${vg}/${newvg}/g" /boot/grub/grub.cfg
    sed -i "s/${vg}/${newvg}/g" /etc/initramfs-tools/conf.d/resume
else
    # no dashes in current name
    vgrename ${vg} ${newvg}
    sed -i "s/${vg}/${newvg}/g" /etc/fstab
    sed -i "s/${vg}/${newvg}/g" /boot/grub/grub.cfg
    sed -i "s/${vg}/${newvg}/g" /etc/initramfs-tools/conf.d/resume
fi

#check files
echo fstab update:
grep ${newvg} /etc/fstab

echo grub.cfg update:
grep ${newvg} /boot/grub/grub.cfg

echo resume update:
grep ${newvg} /etc/initramfs-tools/conf.d/resume

echo update initramfs
update-initramfs -c -k all