This documentation applies only Turris OS 3.x that is no longer present in newly sold routers.
The new documentation is located at https://docs.turris.cz/.
If you want to be sure that updates won't harm your specific configuration, you can choose to delay them until a time when you are ready to install them and have prepared a snapshot, which can go back to. From Turris OS version 3.8, we offer you the option of Update approvals under the Updater tab in the Foris web interface.
(Recommended) - Selecting this option means everything will remain as it was up to now. Updates will be installed as soon as we release them. This is the recommended option, if you don't have any complex settings on your router and you are happy with having Turris OS
always up to date.
Delayed updates - This option lets you delay your update for a specific number of hours. During this set period, the updates won't install automatically and they will only install either after the set time is up or after you have approved them manually. You will be notified about pending updates on the Foris Home page along with other installed packages and also by e-mail, if you have set e-mail notifications (Maintenance → Notification settings → check Enable notifications and fill out Recipient's email). You can then approve the given update in the Updater tab in Foris by clicking Install now.
Foris Home page notifications about pending updates:
Update approval needed - If you select this option, no updates will ever be installed unless you approve them. The catch here is that you also won't be able to install any other packages as long as you want to block the update. When you install other packages, the update will be installed along with them.
Don't forget to click Save after you have selected the desired option.