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If you have a maintenance window or a scheduled outage for a device then you will likely want to suspend alerting for that device during that period.
NMIS has supported this for a long time; NMIS 8.6.2 adds a number of new capabilities, in terms of scheduling such maintenance windows in advance or even recurringly.

Please note that the scope of a scheduled outage is the whole device, ie. no alerting whatsoever takes place for any aspect of the device for the duration of the outage.
Outages do not affect the polling of a device; NMIS does keep track of the device's status and any collected information even during an outage, it just won't produce alerts.

Managing Outage Windows using the GUI

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