Use Azure temporary disk for swap without waagent (on Debian)

install_azure_addswap.sh

cat <<'EOF' | sudo tee /usr/local/sbin/addswap.sh
#!/bin/sh

if [ ! -f /mnt/swapfile ]
then
    /usr/bin/fallocate -l 30G /mnt/swapfile
    /usr/bin/chmod 600 /mnt/swapfile
    /usr/sbin/mkswap /mnt/swapfile
    /usr/sbin/swapon /mnt/swapfile
fi
EOF
sudo chmod 744 /usr/local/sbin/addswap.sh

cat <<'EOF' | sudo tee /etc/systemd/system/addswap.service
[Unit]
Description=Enable 30G swap on Azure temp-disk

[Service]
Type=oneshot
ExecStart=/usr/local/sbin/addswap.sh

[Install]
WantedBy=multi-user.target
EOF
sudo chmod 644 /etc/systemd/system/addswap.service
sudo systemctl enable addswap.service