There are some Nagios checks here for OpenBSD

• check_hw_sensors (check_hw_sensors-1.40.tar.gz)
  Checks the output from sysctl hw.sensors (like sensorsd(8)) for nagios.
• check_bioctl (check_bioctl-1.9.tar.gz)
  Checks the output from bioctl for nagios.
• check_openbgpd (chkck_openbgpd-1.5.tar.gz)
  Checks OpenBGPd Neighbors.

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These finances ensure that OpenBSD will continue to exist, and will remain free for everyone to use and reuse as they see fit.