Rules

ALERT low_memory
  IF (((node_memory_MemTotal - node_memory_MemFree - node_memory_Cached) / (node_memory_MemTotal) * 100)) > 95
  FOR 30s
  LABELS {severity="page"}
  ANNOTATIONS {description="Memory usage in {{ $labels.ip }} is above 95%", summary="{{$labels.category}}/{{$labels.alias}} has low memory"}
ALERT low_disk
  IF node_filesystem_free{fstype!~"rootfs|tmpfs|fuse.lxcfs"} / node_filesystem_size{fstype!~"rootfs|tmpfs|fuse.lxcfs"} < 0.25
  FOR 30s
  LABELS {severity="page"}
  ANNOTATIONS {description="{{ $labels.ip }} has low disk space. More than 95% occupied", summary="{{$labels.category}}/{{$labels.alias}} has low disk space"}
ALERT node_down
  IF up == 0
  FOR 30s
  LABELS {severity="page"}
  ANNOTATIONS {description="{{$labels.ip}} has been down for more than 30 seconds.", summary="{{$labels.category}}/{{$labels.alias}} is down"}