Upgrade Old Ubuntu Server to New LTS
Use sed to update /etc/apt/sources.list
sudo sed -i -e 's/archive.ubuntu.com\|security.ubuntu.com/old-releases.ubuntu.com/g' /etc/apt/sources.list
apt update
apt upgrade
apt dist-upgrade
Use sed to update /etc/apt/sources.list
sudo sed -i -e 's/archive.ubuntu.com\|security.ubuntu.com/old-releases.ubuntu.com/g' /etc/apt/sources.list
apt update
apt upgrade
apt dist-upgrade