如何设置Déjà Dup备份调度时间？修改定时任务方法咨询

Hey there! Let's tackle your Déjà Dup scheduling questions one by one:

Can you set Déjà Dup's automatic backup time? #

Absolutely! The simplest way is right through the graphical interface—no need to dive into config files first. Here's how:

• Open Déjà Dup (search for "Backups" in your app menu)
• Switch to the Schedule tab (labeled "Automatic Backups" in some versions)
• You’ll find options to set backup frequency (daily, weekly, etc.) and a specific start time. Pick a window when you know your cloud drive will be accessible, and that’s it.

Where is Déjà Dup's cron/timer task located? #

Déjà Dup uses different scheduling systems depending on your setup:

• Modern GNOME-based systems (Ubuntu, Fedora, etc.): It relies on systemd user timers instead of traditional cron. You’ll find the relevant files in your user config directory:
  • Timer file: ~/.config/systemd/user/deja-dup-backup.timer
  • Matching service file: ~/.config/systemd/user/deja-dup-backup.service
  • To check the timer’s status, run: systemctl --user list-timers deja-dup-backup.timer
• Older/non-GNOME setups: It may use a user-specific crontab entry. Open your crontab with crontab -e and look for lines starting with deja-dup --backup.

Can you manually modify the schedule? #

Yes, you’ve got a few options—pick the one that fits your comfort level:

Graphical Interface (Recommended) #

Stick to the Schedule tab in Déjà Dup. Adjusting the time here is safest, as it ensures all related configs get updated correctly.

Modify the Systemd Timer #

If you prefer the command line:

1. Open the timer file in a text editor: nano ~/.config/systemd/user/deja-dup-backup.timer
2. Locate the OnCalendar line—it uses systemd’s calendar format (e.g., OnCalendar=daily *-*-* 03:00:00 for 3 AM daily)
3. Update the time to your preferred window, save the file, then reload systemd and restart the timer:

   systemctl --user daemon-reload
   systemctl --user restart deja-dup-backup.timer
   

Modify the Crontab #

If cron is being used:

1. Open your user crontab: crontab -e
2. Find the Déjà Dup backup line (it might look like 0 3 * * * deja-dup --backup)
3. Adjust the cron schedule fields (minute, hour, day, month, weekday) to your desired time. For example, to run at 8 PM every weekday, use 0 20 * * 1-5 deja-dup --backup
4. Save and exit—crontab will apply the changes automatically.

A quick bonus tip: To avoid failed backups when your cloud drive is inaccessible, you can add a pre-check to your backup command. For example, in the systemd service or crontab, replace deja-dup --backup with:

if mountpoint -q /path/to/your/cloud/drive; then deja-dup --backup; fi

This only runs the backup if the drive is mounted.

内容的提问来源于stack exchange，提问作者João Pimentel Ferreira