Implements network alerts

2026-05-04 18:00:10 +00:00 · 2019-07-10 12:43:17 +02:00 · 2019-07-10 12:43:17 +02:00 · 11fa6b5212
commit 11fa6b5212
parent 95a2647390
11 changed files with 355 additions and 58 deletions
--- a/scripts/callbacks/interface/alerts/network.lua
+++ b/scripts/callbacks/interface/alerts/network.lua
@ -0,0 +1,116 @@
+--
+-- (C) 2019 - ntop.org
+--
+
+local dirs = ntop.getDirs()
+package.path = dirs.installdir .. "/scripts/lua/modules/?.lua;" .. package.path
+require "lua_utils"
+require "alert_utils"
+
+alerts_api = require("alerts_api")
+
+local do_trace      = true
+local config_alerts = nil
+local ifname        = nil
+
+-- The function below ia called once (#pragma once)
+function setup(str_granularity)
+   print("alert.lua:setup("..str_granularity..") called\n")
+   ifname = interface.setActiveInterfaceId(tonumber(interface.getId()))
+   config_alerts = getNetworksConfiguredAlertThresholds(ifname, str_granularity)
+
+   -- Load the threshold checking functions
+   package.path = dirs.installdir .. "/scripts/callbacks/interface/alerts/network/?.lua;" .. package.path
+   checks = require("check")
+end
+
+-- #################################################################
+
+-- The function below is called once per network
+local function checkNetworkAlertsThreshold(network_key, network_info, granularity, num_granularity, rules)
+   if do_trace then print("checkNetworkAlertsThreshold()\n") end
+
+   for function_name, params in pairs(rules) do
+      -- IMPORTANT: do not use "local" with the variables below
+      --            as they need to be accessible by the evaluated function
+      threshold_value    = params["edge"]
+      alert_key_name     = params["key"]
+      threshold_operator = params["operator"]
+      metric_name        = params["metric"]
+      threshold_gran     = granularity
+      threshold_num_gran = num_granularity
+      n_info             = network_info
+
+      print("[Alert @ "..granularity.."] ".. network_key .." ["..function_name.."]\n")
+
+      if true then
+         -- This is where magic happens: load() evaluates the string
+         local what = 'return checks.'..function_name..'(metric_name, n_info, threshold_gran, threshold_num_gran)'
+         local func, err = load(what, 't')
+
+         if func then
+            local ok, value = pcall(func)
+
+            if ok then
+               local alarmed = false
+               local network_alert = alerts_api:newAlert({entity = "network", type = "threshold_cross", severity = "error"})
+
+               if do_trace then print("Execution OK. value: "..tostring(value)..", operator: "..threshold_operator..", threshold: "..threshold_value.."]\n") end
+
+               threshold_value = tonumber(threshold_value)
+
+               if threshold_operator == "lt" then
+                  if value < threshold_value then alarmed = true end
+               else
+                  if value > threshold_value then alarmed = true end
+               end
+
+               if alarmed then
+                  if interface.storeTriggeredAlert(alert_key_name, num_granularity) then
+                     -- IMPORTANT: uncommenting the line below break all
+                     -- network_alert:trigger(network_key, "Network "..network_key.." crossed threshold "..metric_name)
+                     print("Trigger alert [value: "..tostring(value).."]\n")
+                  end
+               else
+                  if interface.releaseTriggeredAlert(alert_key_name, num_granularity) then
+                     print("DON'T trigger alert [value: "..tostring(value).."]\n")
+                     -- network_alert:release(network_key)
+                  end
+               end
+            else
+               if do_trace then print("Execution error:  "..tostring(rc).."\n") end
+            end
+         else
+            print("Compilation error:", err)
+         end
+      end
+
+      print("=============\n")
+   end
+end
+
+-- #################################################################
+
+-- The function below is called once per local network
+function checkNetworkAlerts(granularity)
+   local info = network.getNetworkStats()
+   local network_key = info and info.network_key
+
+   if not network_key then
+      return
+   end
+
+   local network_alert = config_alerts[network_key]
+   local num_granularity = granularity2id(granularity)
+
+   -- specific network alerts
+   if network_alert and table.len(network_alert) > 0 then
+      checkNetworkAlertsThreshold(network_key, info, granularity, num_granularity, network_alert)
+   end
+
+   -- generic network alerts
+   network_alert = config_alerts["local_networks"]
+   if network_alert and table.len(network_alert) > 0 then
+      checkNetworkAlertsThreshold(network_key, info, granularity, num_granularity, network_alert)
+   end
+end