Backups
Backup is the most important job on the list. Systems fail eventually, and a backup is the difference between an afternoon's work and starting again from nothing.
What is in a backup
A backup captures everything you have set up: your devices and the names you gave them, your scenes and instincts, your calibration figures, your dashboards, your history and your licence.
Device firmware is not included, and does not need to be. If a device fails you fit a new one and flash the same firmware version. New hardware has a new address, so it needs adding to your system again.
If Sensa supplied your unit
Your system backs itself up. There is nothing to set up and nothing to remember.
- Every night at 03:00. You keep the three most recent nightly backups, and the oldest is removed as a new one arrives.
- Before every update. A snapshot is taken just before your system updates itself, so there is always a recent point to return to. The update waits for it to finish, which takes several minutes, and only then installs anything. These are kept, and are not counted against the three nightly copies. See Updates.
- Whenever you ask. Press Back up now on the Backup tab.
Every backup is named for what caused it, so the list reads plainly: Overnight backup, Manual backup, or Before update to 1.0.0.
Everything is encrypted
Every backup your system takes is encrypted, including the copy that stays on the unit. A backup is only useful once it is somewhere else, and every way of getting one off the vehicle turns it into a copy that has left your control.
Your system holds the key that unlocks them. The only copy of that key outside the vehicle is the emergency kit, so download it and keep it somewhere safe. Without it, a backup cannot be opened on any other machine.
Press Download emergency kit on the Backup tab and store the file outside your vehicle: a password manager, a cloud drive, or a printed copy with your vehicle paperwork. If you lose both the unit and the kit, the backups you had copied elsewhere cannot be opened.
The Backup tab
Sign in as admin and open the Sensa Settings panel, then the Backup tab.
The top card tells you the state of things: when the last backup ran, when the next one is due, and the schedule in plain words, for example "Daily at 03:00, keeping 3". If nothing is scheduled it says so rather than promising a run that will not happen.
Below it is the list of stored backups, newest first:
| Column | What it tells you |
|---|---|
| Backup | What it was named for, and a pin if it is being kept |
| Location | Where it is stored. Today that reads "This device" |
| Created | When it was taken, in your own time |
| Size | How large it is |
A backup still being written shows Creating… until it finishes. Back up now is unavailable while one is in progress, because your system will only write one at a time.
Everyday tablet logins can see the tab and the list, but cannot run, restore or delete anything. See Accounts and access.
Putting a backup back
Each row in the list has a Restore button.
Restoring puts everything back to how it was when that backup was taken: your devices, dashboards, settings and history. Anything you have changed since is lost. Your system restarts to do it, which takes several minutes, and the page reconnects on its own when it comes back.
Because it cannot be undone, Restore asks you to confirm in a dialog naming the backup and when it was taken, rather than a button you might press twice by reflex.
A few things Sensa checks before it starts:
- A backup or a restore already running. You are asked to wait rather than told something vague went wrong.
- The encryption key. If a backup was made under a different key, for example one taken from another unit, it cannot be unlocked here and retrying will not help.
If something goes wrong after the point of no return, the Backup tab shows what happened when your system comes back up.
If you run Sensa on your own Home Assistant
On an Enthusiast or DIY system you look after your own backups, and Home Assistant's own backup screen is the place to do it. The Sensa Backup tab is not offered, because writing your Home Assistant's settings from underneath you would not be right.
- Open Settings > Backups
- Click Create backup and choose Full backup
- Set a password, which becomes the encryption key
- Save the backup file somewhere safe: a USB stick, a cloud drive, or a NAS
- Save the password in a password manager. Without it the backup cannot be opened
Take a backup once a month, and after every meaningful change to your setup.
Keeping a copy off the vehicle
A backup that only exists on the unit does not survive the unit. Whichever system you have, keep at least one copy somewhere else, and refresh it after any meaningful change.
To recover from a hardware failure, swap hardware, or set up an offsite copy, follow the Recovery steps.