netdata/health/health.d/backend.conf

# make sure we are sending data to backend

   alarm: backend_last_buffering
      on: netdata.backend_metrics
    calc: $now - $last_collected_t
   units: seconds ago
   every: 10s
    warn: $this > (($status >= $WARNING)  ? ($update_every) : ( 5 * $update_every))
    crit: $this > (($status == $CRITICAL) ? ($update_every) : (60 * $update_every))
   delay: down 5m multiplier 1.5 max 1h
    info: number of seconds since the last successful buffering of backend data
      to: dba

   alarm: backend_metrics_sent
      on: netdata.backend_metrics
   units: %
    calc: abs($sent) * 100 / abs($buffered)
   every: 10s
    warn: $this != 100
   delay: down 5m multiplier 1.5 max 1h
    info: percentage of metrics sent to the backend server
      to: dba

   alarm: backend_metrics_lost
      on: netdata.backend_metrics
   units: metrics
    calc: abs($lost)
   every: 10s
    crit: ($this != 0) || ($status == $CRITICAL && abs($sent) == 0)
   delay: down 5m multiplier 1.5 max 1h
    info: number of metrics lost due to repeating failures to contact the backend server
      to: dba

# this chart has been removed from netdata
#   alarm: backend_slow
#      on: netdata.backend_latency
#   units: %
#    calc: $latency * 100 / ($update_every * 1000)
#   every: 10s
#    warn: $this > 50
#    crit: $this > 100
#   delay: down 5m multiplier 1.5 max 1h
#    info: the percentage of time between iterations needed by the backend time to process the data sent by netdata
#      to: dba