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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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• NMIS checks for current outages whenever alerts or escalations are processed; If an outage is current, then alerting is suppressed.
• NMIS does, however, not suspend polling during an outage.
• While an outage is current and a node does not respond to ICMP or SNMP, then the KPI's for that poll are set to U (unknown, which prevents them from contributing to averages), this is so the overall reachability and availability results are not reduced for that node which has a planned outage.  The KPI's included in this exclusion are:
  • reachability
  • availability
  • intfTotal
  • responsetime
  • health
  • loss
• Furthermore, the state of nodes with current outages does not contribute to the overall health metrics and KPIs, which helps with reporting statistics so your teams performance will look better!
• In version 8.6.2 and newer, the per-node status view displays current and scheduled/future outages prominently.
• In version 8.6.2 and newer, the events Planned Outage Open and Planned Outage Closed are raised for each polled device that enters or leaves an outage window.
• In version 8.6.2 and newer NMIS tracks the state of outages per node and shows a translucent overlay on the node health graph for each outage.

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