Developer Centric Virtual Private Servers

Systemd provides a powerful way to schedule recurring maintenance tasks without relying on cron.
By creating a simple service and timer, you can automatically update your system every night — fully noninteractively — with logs stored in journalctl.

This method is ideal for servers, VPS environments, and long-running workstations that need consistent, unattended updates.

1. Create the Upgrade Script

First, create a reusable script at /usr/local/sbin/auto-upgrade.sh:

sudo tee /usr/local/sbin/auto-upgrade.sh > /dev/null <<'EOF'
#!/bin/bash
set -e
LOGFILE="/var/log/auto-upgrade.log"
{
  echo "=== Auto-upgrade started: $(date) ==="
  env DEBIAN_FRONTEND=noninteractive APT_LISTCHANGES_FRONTEND=none apt-get update -y
  env DEBIAN_FRONTEND=noninteractive APT_LISTCHANGES_FRONTEND=none apt-get \
    -o Dpkg::Options::="--force-confdef" \
    -o Dpkg::Options::="--force-confold" -y dist-upgrade
  apt-get -y autoremove
  apt-get -y autoclean
  echo "=== Auto-upgrade finished: $(date) ==="
} >> "$LOGFILE" 2>&1
EOF

sudo chmod +x /usr/local/sbin/auto-upgrade.sh

This script:

Updates all packages noninteractively.
Keeps existing configuration files.
Logs all actions to /var/log/auto-upgrade.log.

2. Create the Systemd Service

Save this file as /etc/systemd/system/auto-upgrade.service:

[Unit]
Description=Automatic Ubuntu 24.04 system upgrade
After=network-online.target
Wants=network-online.target

[Service]
Type=oneshot
ExecStart=/usr/local/sbin/auto-upgrade.sh
Nice=10
IOSchedulingClass=idle
StandardOutput=journal
StandardError=journal

[Install]
WantedBy=multi-user.target

Explanation:

Runs only once per trigger (Type=oneshot).
Defers until the network is available.
Runs with lower CPU and I/O priority to minimize system impact.
Outputs to journalctl for easy inspection (journalctl -u auto-upgrade.service).

3. Add the Systemd Timer

Create /etc/systemd/system/auto-upgrade.timer:

[Unit]
Description=Run automatic Ubuntu 24.04 upgrade daily

[Timer]
OnCalendar=03:00
Persistent=true
RandomizedDelaySec=300

[Install]
WantedBy=timers.target

What it does:

Triggers the upgrade daily at 3:00 AM.
Adds a random delay of up to 5 minutes to prevent simultaneous updates on clusters.
Persistent=true ensures missed runs are executed once the system is back online.

4. Enable and Start the Timer

Run the following commands:

sudo systemctl daemon-reload
sudo systemctl enable --now auto-upgrade.timer

You can check its status anytime:

systemctl status auto-upgrade.timer

And view logs for recent runs:

journalctl -u auto-upgrade.service -n 50

5. (Optional) Auto-Reboot After Kernel Upgrades

If you want automatic reboots after updates that require them, enable it:

sudo apt-get install -y unattended-upgrades
sudo sed -i 's|//Unattended-Upgrade::Automatic-Reboot "false";|\
Unattended-Upgrade::Automatic-Reboot "true";|' /etc/apt/apt.conf.d/50unattended-upgrades

Conclusion

With this setup, your Ubuntu 24.04 system will:

Automatically fetch and apply updates daily.
Log all actions safely.
Run efficiently during low-load hours.