Location: System Configuration -> System Status -> Maintenance Mode
There is a possibility to put the system into maintenance mode that restricts normal (non-admin) users from logging into the system during code and database upgrades.
Maintenance configuration page is available under the System Configuration -> System Status -> Maintenance Mode. To enable Maintenance Mode:
Open Edit Settings window;
Specify the Expected Downtime — period, which defines how long the system is going to be unavailable, the countdown timer will be shown for users;
In the Allow List select the users, who should be able to log into the system during the downtime period (note, that system administrator always has the access no matter if he is selected in the allow list or not);
Specify URL for External Maintenance Page if you want to use custom maintenance pages (about that in a moment);
Click Put system into maintenance mode.

Fig.19.: Maintenance Mode window
When the maintenance mode is enabled, normal users, who are not present in the allow list will be restricted from logging in. Maintenance mode screen will be shown for them.

Fig.20.: Maintenance Mode is active, user sees this page on attempt to log in
Custom maintenance pages can be placed to /web/WEB-INF/jsp/commonLegacy/custom
folder on file structure of the server with installed Encodify system. In this case relative path to the page should be specified in maintenance mode settings: /common/custom/
Full external link including the transfer protocol should be specified if you want redirect users to the page on the other domain, e.g. http://sitename.com
Current functionality is duplicated by independent jsp-script, so system administrator can enable/disable maintenance mode without being logged to the system.
The script can be accessed by the link:
http://<serverURL>/<worker>/common/scripts/SystemMaintenanceMode.jsp
If the systems doesn't display the above message, it's possible to do a workaround:
For the external maintenance page, use:
Baseurl https://m.encode.dk/
Request param time, with information about time.
Request param site, with url to site to redirect back to.
So it will look like:https://m.encode.dk/?time=10:15%2030/7-2021&site=https://SITENAME.encode.dk/