Expanding on this, you can do it manually by right clicking on any node in the Objects tree (Entire Network if so desired) and there is an option for Maintenance. You can Enter, Leave or Schedule maintenance. I do this when I am updating my servers or otherwise taking them offline. Usually I will schedule maintenance for the group I am working on but set it for twice what my maintenance window is. My procedure is to leave maintenance when I am done (hopefully early) but if I forget, it will happen on it's own. That way if go over my time, I don't start getting a bunch of alarms
To do it automatically, choose Configuration/Scheduled Tasks. Here you can create a scheduled task to enter maintenance mode and then another task to leave maintenance mode. I have a few servers that update on their own or have a monitored process that resets on a schedule, so I use scheduled tasks for those instances.
