update.sh

#!/bin/bash -eux

# Disable the release upgrader
echo "==> Disabling the release upgrader"
sed -i.bak 's/^Prompt=.*$/Prompt=never/' /etc/update-manager/release-upgrades

echo "==> Checking version of Ubuntu"
. /etc/lsb-release

if [[ $DISTRIB_RELEASE == 16.04 || $DISTRIB_RELEASE == 18.04 ]]; then
  echo "==> Disabling periodic apt upgrades"
  echo 'APT::Periodic::Enable "0";' >> /etc/apt/apt.conf.d/10periodic
fi

echo "==> Updating list of repositories"
# apt-get update does not actually perform updates, it just downloads and indexes the list of packages
apt-get -y update

if [[ $UPDATE  =~ true || $UPDATE =~ 1 || $UPDATE =~ yes ]]; then
    echo "==> Performing dist-upgrade (all packages and kernel)"
    apt-get -y dist-upgrade --force-yes
    reboot
    sleep 60
fi