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# ---- List active timers ----
systemctl list-timers
systemctl list-timers --all    # Include inactive timers

# ---- Create a systemd timer ----

# Step 1: Create the service unit
# sudo nano /etc/systemd/system/mybackup.service

# Contents of mybackup.service:
# [Unit]
# Description=Daily database backup
# After=network.target
#
# [Service]
# Type=oneshot
# User=backup
# ExecStart=/usr/local/bin/backup_db.sh
# StandardOutput=journal
# StandardError=journal

# Step 2: Create the timer unit
# sudo nano /etc/systemd/system/mybackup.timer

# Contents of mybackup.timer:
# [Unit]
# Description=Run daily database backup at 2 AM
# Requires=mybackup.service
#
# [Timer]
# OnCalendar=*-*-* 02:00:00
# Persistent=true
# RandomizedDelaySec=300
#
# [Install]
# WantedBy=timers.target

# Step 3: Enable and start the timer
sudo systemctl daemon-reload
sudo systemctl enable --now mybackup.timer
sudo systemctl status mybackup.timer

# ---- OnCalendar examples ----
# Daily at 2:00 AM:      *-*-* 02:00:00
# Every Monday at 6 AM:  Mon *-*-* 06:00:00
# Every 15 minutes:      *:0/15
# Hourly:                hourly  (shorthand)
# Daily:                 daily
# Weekly:                weekly
# Monthly:               monthly

# ---- Timer management ----
sudo systemctl start mybackup.timer       # Start now
sudo systemctl stop mybackup.timer        # Stop timer
sudo systemctl disable mybackup.timer     # Disable on boot

# Run the associated service immediately (test)
sudo systemctl start mybackup.service

# View logs for the service
journalctl -u mybackup.service
journalctl -u mybackup.service --since "1 hour ago"