Rename LVM Volume Group

rename_volume_group.sh

#!/bin/bash

# Rename LVM Volume Group
# (c)https://askubuntu.com/a/900532
# 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
read -p "Enter new hostname: " newhostname

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

update-initramfs -u -k all