To disable a unit:

Click on the unit in the units list

Select the Edit tab

Select the disabled check box and then click on update button.

The unit will be disabled successfully. Disabled units are the units that are temporarily unavailable for monitoring. To working with such units is stopped until they are activated. Disabled a unit may be necessary in case it is used, for instance and a limited period of time and does not need to be monitored the rest of the time.