FAQ. Problems with object activity
In the equipment list - some/all equipment is shown in red as inactive. Open the equipment card - ping is performed. The equipment in the list turns green. After 15 minutes it's red again.
The web-interface of the system itself does not control which equipment is active and which is not. Only when the user acts actively (e.g. by opening the equipment card) does the system find out what is wrong with the device - is it active or not? Read the article "Activity".
To have always up-to-date information about the hardware you need to put modules which do that. In particular, the usm_checker module. It is this module which you'd better use and put into your system cron. It checks whether the device is active and then the user will always see the current information in the web-interface.