NMIS has multiple poll cycles, every 5 minutes an SNMP poll cycle is run, this is also when services are polled.  If fpingd.pl is being used it will poll nodes every ~1 minute by default.  It is recommended to use fpingd.pl when using NMIS, which will use ICMP to poll nodes with higher frequency than the regular NMIS poll cycle.  During the fping poll cycle, the escalation process is also run, this helps to ensure that notifications are sent out with minimal delay, and enables highly granular escalation policies.

NMIS will try to make sure it's own fpingd.pl is running every time a collect or update is run if configured to use it (detailed below).  If fpingd is not enabled or the loss value for the node to ping cannot be found in the fping status file nmis-fping.nmis then NMIS will run a ping of it's own.  This code can be found in nmis.pl in sub runPing.

fpingd

fpingd is enabled by default, the config setting (in Config.nmis) to control this is:

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