diff --git a/include/Ntop.h b/include/Ntop.h
index 56ff1a3055..efe332385f 100644
--- a/include/Ntop.h
+++ b/include/Ntop.h
@@ -355,6 +355,7 @@ class Ntop {
   inline NagiosManager*    getNagios()               { return(nagios_manager);      };
 #endif
 #endif
+  void checkSNMPDeviceAlerts(ScriptPeriodicity p);
   void lua_periodic_activities_stats(NetworkInterface *iface, lua_State* vm);
   void getUsers(lua_State* vm);
   bool isUserAdministrator(lua_State* vm);
diff --git a/scripts/callbacks/alert_defs/alert_port_load_threshold_exceeded.lua b/scripts/callbacks/alert_defs/alert_port_load_threshold_exceeded.lua
index bb61f228e6..a27d0b1b25 100644
--- a/scripts/callbacks/alert_defs/alert_port_load_threshold_exceeded.lua
+++ b/scripts/callbacks/alert_defs/alert_port_load_threshold_exceeded.lua
@@ -5,13 +5,17 @@
 local function snmpPortLoadThresholdFormatter(ifid, alert, info)
   if ntop.isPro() then require "snmp_utils" end
 
-  return(i18n("alerts_dashboard.snmp_port_load_threshold_exceeded_message",
-    {device = info.device,
+  local fmt = {
+     device = info.device,
      port = info.interface_name or info.interface,
      url = snmpDeviceUrl(info.device),
      port_url = snmpIfaceUrl(info.device, info.interface),
-     port_load = info.interface_load,
-     direction = ternary(info.interface_load, "RX", "TX")}))
+     in_load = info.in_load,
+     out_load = info.out_load,
+     threshold = info.load_threshold,
+  }
+
+  return(i18n("alerts_dashboard.snmp_port_load_threshold_exceeded_message", fmt))
 end
 
 -- #######################################################
diff --git a/scripts/callbacks/system/snmp_device.lua b/scripts/callbacks/system/snmp_device.lua
new file mode 100644
index 0000000000..43f8956754
--- /dev/null
+++ b/scripts/callbacks/system/snmp_device.lua
@@ -0,0 +1,100 @@
+--
+-- (C) 2019 - ntop.org
+--
+
+local dirs = ntop.getDirs()
+package.path = dirs.installdir .. "/scripts/lua/modules/?.lua;" .. package.path
+require "lua_utils"
+require "alert_utils"
+require "snmp_utils"
+
+local alerts_api = require("alerts_api")
+local user_scripts = require("user_scripts")
+local alert_consts = require("alert_consts")
+
+local do_benchmark = true          -- Compute benchmarks and store their results
+local do_print_benchmark = false   -- Print benchmarks results to standard output
+local do_trace = false             -- Trace lua calls
+
+local config_alerts = nil
+local available_modules = nil
+local ifid = nil
+local snmp_device_entity = alert_consts.alert_entities.snmp_device.entity_id
+
+-- The function below ia called once (#pragma once)
+function setup(str_granularity)
+   if do_trace then print("alert.lua:setup("..str_granularity..") called\n") end
+
+   interface.select(getSystemInterfaceId())
+   ifid = interface.getId()
+   local ifname = getInterfaceName(tostring(ifid))
+
+   -- Load the threshold checking functions
+   available_modules = user_scripts.load(user_scripts.script_types.snmp_device, ifid, "snmp_device", nil --[[ load all hooks --]], nil, do_benchmark)
+
+   -- config_alerts = getNetworksConfiguredAlertThresholds(ifname, str_granularity, available_modules.modules)
+end
+
+-- #################################################################
+
+-- The function below ia called once (#pragma once)
+function teardown(str_granularity)
+   if(do_trace) then print("alert.lua:teardown("..str_granularity..") called\n") end
+
+   user_scripts.teardown(available_modules, do_benchmark, do_print_benchmark)
+end
+
+-- #################################################################
+
+local cur_granularity
+
+local function snmp_device_interfaces_check_alerts(snmp_device, deadline)
+   local do_call = true
+   local granularity = cur_granularity
+
+   local device_ip         = snmp_device.get_device_info()["host"]
+   local device_interfaces = snmp_device.get_device()["interfaces"] or {}
+   local device_if_status  = snmp_device.get_device()["interfaces_status"] or {}
+   local device_counters   = snmp_device.get_device()["counters"] or {}
+   local device_bridge     = snmp_device.get_device()["bridge"] or {}
+
+   -- For each callback that needs to be called on the interfaces...
+   for mod_key, hook_fn in pairs(available_modules.hooks["snmpDeviceInterface"]) do
+      local check = available_modules.modules[mod_key]
+
+      -- For each interface of the current device...
+      for snmp_interface_index, snmp_interface in pairs(device_interfaces) do
+	 local entity_info = alerts_api.snmpInterfaceEntity(device_ip, snmp_interface_index)
+	 local info = {
+	    snmp_device_ip = device_ip,
+	    snmp_interface = snmp_interface,
+	    if_status = device_if_status[snmp_interface_index],
+	    if_counters = device_counters[snmp_interface_index],
+	    if_bridge = device_bridge[snmp_interface_index]}
+
+	 if(do_call) then
+	    hook_fn({
+	    	  granularity = granularity,
+	    	  alert_entity = entity_info,
+	    	  entity_info = info,
+	    	  cur_alerts = cur_alerts,
+	    	  alert_config = config,
+	    	  user_script = check,
+	    })
+	 end
+      end
+   end
+
+   return true
+end
+
+-- #################################################################
+
+-- The function below is called once per local snmp_device
+function checkAlerts(granularity)
+   cur_granularity = granularity
+
+   if not table.empty(available_modules.hooks["snmpDeviceInterface"]) then
+      local in_time = foreachSNMPDevice(snmp_device_interfaces_check_alerts, nil --[[ snmp_rrds_enabled --]], nil --[[ deadline --]])
+   end
+end
diff --git a/scripts/locales/en.lua b/scripts/locales/en.lua
index b3f5e69784..d6b2ecc81f 100644
--- a/scripts/locales/en.lua
+++ b/scripts/locales/en.lua
@@ -381,7 +381,7 @@ local lang = {
     ["snmp_port_errors"] = "Interface Errors",
     ["snmp_port_errors_increased"] = "Discard/error counters increased on interface <a href=\"%{port_url}\">%{port}</a> on SNMP device <a href=\"%{url}\">%{device}</a>",
     ["snmp_port_load_threshold_exceeded"] = "Interface Load Threshold Exceeded",
-    ["snmp_port_load_threshold_exceeded_message"] = "%{direction} load is %{port_load}%% on interface <a href=\"%{port_url}\">%{port}</a> on SNMP device <a href=\"%{url}\">%{device}</a>",
+    ["snmp_port_load_threshold_exceeded_message"] = "Load threshold exceeded on interface <a href=\"%{port_url}\">%{port}</a> on SNMP device <a href=\"%{url}\">%{device}</a> [threshold: %{threshold}%%][IN load: %{in_load}%%][OUT load: %{out_load}%%]",
     ["snmp_port_status_change"] = "Interface Status Change",
     ["starting_on"] = "starting on",
     ["submit"] = "Update Dashboard",
diff --git a/scripts/lua/modules/alert_utils.lua b/scripts/lua/modules/alert_utils.lua
index 516fd4e090..18657835d0 100644
--- a/scripts/lua/modules/alert_utils.lua
+++ b/scripts/lua/modules/alert_utils.lua
@@ -2873,39 +2873,6 @@ local function notify_ntopng_status(started)
   return(alerts_api.store(entity_info, type_info))
 end
 
-function notify_snmp_device_interface_status_change(snmp_host, snmp_interface)
-  local entity_info = alerts_api.snmpInterfaceEntity(snmp_host, snmp_interface["index"])
-  local type_info = alerts_api.snmpInterfaceStatusChangeType(snmp_host, snmp_interface["index"], snmp_interface["name"], snmp_interface["status"])
-
-  interface.select(getSystemInterfaceId())  
-  return(alerts_api.store(entity_info, type_info))
-end
-
-function notify_snmp_device_interface_duplexstatus_change(snmp_host, snmp_interface)
-  local entity_info = alerts_api.snmpInterfaceEntity(snmp_host, snmp_interface["index"])
-  local type_info = alerts_api.snmpInterfaceDuplexStatusChangeType(snmp_host, snmp_interface["index"], snmp_interface["name"], snmp_interface["duplexstatus"])
-
-  interface.select(getSystemInterfaceId())
-  return(alerts_api.store(entity_info, type_info))
-end
-
-function notify_snmp_device_interface_errors(snmp_host, snmp_interface)
-  local entity_info = alerts_api.snmpInterfaceEntity(snmp_host, snmp_interface["index"])
-  local type_info = alerts_api.snmpInterfaceErrorsType(snmp_host, snmp_interface["index"], snmp_interface["name"])
-
-  interface.select(getSystemInterfaceId())
-  return(alerts_api.store(entity_info, type_info))
-end
-
-function notify_snmp_device_interface_load_threshold_exceeded(snmp_host, snmp_interface, interface_load, in_direction)
-  local entity_info = alerts_api.snmpInterfaceEntity(snmp_host, snmp_interface["index"])
-  local type_info = alerts_api.snmpPortLoadThresholdExceededType(snmp_host, snmp_interface["index"], snmp_interface["name"],
-    interface_load, in_direction)
-
-  interface.select(getSystemInterfaceId())
-  return(alerts_api.store(entity_info, type_info))
-end
-
 function notify_ntopng_start()
    return(notify_ntopng_status(true))
 end
diff --git a/scripts/lua/modules/alerts_api.lua b/scripts/lua/modules/alerts_api.lua
index 6dde6dedbd..dc1716ca41 100644
--- a/scripts/lua/modules/alerts_api.lua
+++ b/scripts/lua/modules/alerts_api.lua
@@ -763,55 +763,92 @@ end
 
 -- ##############################################
 
-function alerts_api.snmpInterfaceStatusChangeType(device, interface, interface_name, status)
-  return({
-    alert_type = alert_consts.alert_types.alert_port_status_change,
-    alert_severity = alert_consts.alert_severities.info,
-    alert_type_params = {
-      device = device, interface = interface,
-      interface_name = interface_name, status = status,
-    },
-  })
+function alerts_api.snmpInterfaceStatusChangeType(snmp_interface_info, device, interface, interface_name, status)
+   local snmp_interface_index  = snmp_interface_info["snmp_interface"]["index"]
+   local snmp_interface_name   = snmp_interface_info["snmp_interface"]["name"]
+   local snmp_interface_status = snmp_interface_info["if_status"]["status"]
+   local snmp_device_ip = snmp_interface_info["snmp_device_ip"]
+
+   local res = {
+      alert_type = alert_consts.alert_types.alert_port_status_change,
+      alert_severity = alert_consts.alert_severities.info,
+      alert_type_params = {
+	 device = snmp_device_ip,
+	 interface = snmp_interface_index,
+	 interface_name = snmp_interface_name,
+	 status = snmp_interface_status,
+      },
+   }
+
+   return res
 end
 
 -- ##############################################
 
-function alerts_api.snmpInterfaceDuplexStatusChangeType(device, interface, interface_name, status)
-  return({
-    alert_type = alert_consts.alert_types.alert_port_duplexstatus_change,
-    alert_severity = alert_consts.alert_severities.warning,
-    alert_type_params = {
-      device = device, interface = interface,
-      interface_name = interface_name, status = status,
-    },
-  })
+function alerts_api.snmpInterfaceDuplexStatusChangeType(snmp_interface_info)
+   local snmp_interface_index = snmp_interface_info["snmp_interface"]["index"]
+   local snmp_interface_name = snmp_interface_info["snmp_interface"]["name"]
+   local snmp_interface_duplexstatus = snmp_interface_info["if_status"]["duplexstatus"]
+   local snmp_device_ip = snmp_interface_info["snmp_device_ip"]
+
+   local res = {
+      alert_type = alert_consts.alert_types.alert_port_duplexstatus_change,
+      alert_severity = alert_consts.alert_severities.warning,
+      alert_type_params = {
+	 device = snmp_device_ip,
+	 interface = snmp_interface_index,
+	 interface_name = snmp_interface_name,
+	 status = snmp_interface_duplexstatus,
+      },
+   }
+
+   return res
 end
 
 -- ##############################################
 
-function alerts_api.snmpInterfaceErrorsType(device, interface, interface_name)
-  return({
-    alert_type = alert_consts.alert_types.alert_port_errors,
-    alert_severity = alert_consts.alert_severities.info,
-    alert_type_params = {
-      device = device, interface = interface,
-      interface_name = interface_name,
-    },
-  })
+function alerts_api.snmpInterfaceErrorsType(snmp_interface_info)
+   local snmp_interface_index = snmp_interface_info["snmp_interface"]["index"]
+   local snmp_interface_name = snmp_interface_info["snmp_interface"]["name"]
+   local snmp_device_ip = snmp_interface_info["snmp_device_ip"]
+
+   local res = {
+      alert_type = alert_consts.alert_types.alert_port_errors,
+      alert_severity = alert_consts.alert_severities.info,
+      alert_type_params = {
+	 device = snmp_device_ip,
+	 interface = snmp_interface_index,
+	 interface_name = snmp_interface_name,
+      },
+   }
+
+   return res
 end
 
 -- ##############################################
 
-function alerts_api.snmpPortLoadThresholdExceededType(device, interface, interface_name, interface_load, in_direction)
-  return({
-    alert_type = alert_consts.alert_types.alert_port_load_threshold_exceeded,
-    alert_severity = alert_consts.alert_severities.warning,
-    alert_type_params = {
-      device = device, interface = interface,
-      interface_name = interface_name,
-      interface_load = interface_load, in_direction = in_direction,
-    },
-  })
+function alerts_api.snmpPortLoadThresholdExceededType(snmp_interface_info)
+   local snmp_interface_index = snmp_interface_info["snmp_interface"]["index"]
+   local snmp_interface_name = snmp_interface_info["snmp_interface"]["name"]
+   local snmp_device_ip = snmp_interface_info["snmp_device_ip"]
+   local in_port_load = snmp_interface_info["in_port_load"]
+   local out_port_load = snmp_interface_info["out_port_load"]
+   local load_threshold = snmp_interface_info["load_threshold"]
+
+   local res = {
+      alert_type = alert_consts.alert_types.alert_port_load_threshold_exceeded,
+      alert_severity = alert_consts.alert_severities.warning,
+      alert_type_params = {
+	 device = snmp_device_ip,
+	 interface = snmp_interface_index,
+	 interface_name = snmp_interface_name,
+	 in_load = in_port_load,
+	 out_load = out_port_load,
+	 load_threshold = load_threshold,
+      },
+   }
+
+   return res
 end
 
 -- ##############################################
@@ -939,6 +976,21 @@ end
 
 -- ##############################################
 
+-- TODO: comment
+function alerts_api.snmp_device_interface_check_function(params)
+  local check_res = params.user_script.snmp_device_interface_check(params.granularity, params.entity_info)
+
+  if check_res then
+     local type_builder = params.user_script.type_builder
+
+     local check_type = type_builder(params.entity_info)
+
+     return alerts_api.store(params.alert_entity, check_type)
+  end
+end
+
+-- ##############################################
+
 -- An alert check function which performs threshold checks of a value
 -- against a configured threshold and generates a threshold_cross alert
 -- if the value is above the threshold.
diff --git a/scripts/lua/modules/user_scripts.lua b/scripts/lua/modules/user_scripts.lua
index 150225492e..a344033ca8 100644
--- a/scripts/lua/modules/user_scripts.lua
+++ b/scripts/lua/modules/user_scripts.lua
@@ -38,6 +38,9 @@ user_scripts.script_types = {
   }, traffic_element = {
     parent_dir = "interface",
     hooks = {"min", "5mins", "hour", "day"},
+  }, snmp_device = {
+    parent_dir = "system",
+    hooks = {"snmpDeviceInterface"},
   }, syslog = {
     parent_dir = "syslog",
     hooks = {"handleEvent"},
@@ -70,7 +73,7 @@ local benchmarks = {}
 function user_scripts.getSubdirectoryPath(script_type, subdir, is_pro)
   local prefix = ternary(is_pro, PRO_CALLBACKS_DIR, CALLBACKS_DIR)
   local path
-  
+
   if not isEmptyString(subdir) and subdir ~= "." then
     path = string.format("%s/%s/%s", prefix, script_type.parent_dir, subdir)
   else
@@ -465,6 +468,7 @@ function user_scripts.load(script_type, ifid, subdir, hook_filter, ignore_disabl
                elseif(rv.hooks[hook] == nil) then
                   traceError(TRACE_WARNING, TRACE_CONSOLE, string.format("Unknown hook '%s' in module '%s'", hook, user_script.key))
                else
+
 		  if do_benchmark then
 		     rv.hooks[hook][user_script.key] = benchmark_init(subdir, user_script.key, hook, hook_fn)
 		  else
diff --git a/scripts/lua/test_alerts.lua b/scripts/lua/test_alerts.lua
index 31d7994a12..190d4f4d2e 100644
--- a/scripts/lua/test_alerts.lua
+++ b/scripts/lua/test_alerts.lua
@@ -26,5 +26,10 @@ interface.checkNetworksAlertsMin()
 -- checks the current interface alerts
 interface.checkInterfaceAlertsMin()
 
+--require "snmp_utils"
+--run_5min_snmp_caching(600)
+--dofile(dirs.installdir .. "/pro/scripts/callbacks/system/5min.lua")
+--ntop.checkSNMPDeviceAlerts5Min()
+
 dofile(dirs.installdir .. "/scripts/lua/inc/footer.lua")
 
diff --git a/src/AlertCheckLuaEngine.cpp b/src/AlertCheckLuaEngine.cpp
index 9655fa75d3..746d2b9148 100644
--- a/src/AlertCheckLuaEngine.cpp
+++ b/src/AlertCheckLuaEngine.cpp
@@ -44,6 +44,9 @@ AlertCheckLuaEngine::AlertCheckLuaEngine(AlertEntity alert_entity, ScriptPeriodi
   case alert_entity_flow:
     lua_file = "flow.lua";
     break;
+  case alert_entity_snmp_device:
+    lua_file = "snmp_device.lua";
+    break;
   default:
     /* Example: lua_file = "generic.lua" to handle a generic entity */
     break;
@@ -51,8 +54,9 @@ AlertCheckLuaEngine::AlertCheckLuaEngine(AlertEntity alert_entity, ScriptPeriodi
 
   if(lua_file) {
     snprintf(script_path, sizeof(script_path),
-	     "%s/callbacks/interface/%s",
+	     "%s/callbacks/%s/%s",
 	     ntop->getPrefs()->get_scripts_dir(),
+	     iface ? "interface" : "system",
 	     lua_file);
     ntop->fixPath(script_path);
 
diff --git a/src/LuaEngine.cpp b/src/LuaEngine.cpp
index a0b1206013..027d663ba5 100644
--- a/src/LuaEngine.cpp
+++ b/src/LuaEngine.cpp
@@ -291,7 +291,7 @@ static int ntop_set_active_interface_id(lua_State* vm) {
   ntop->getTrace()->traceEvent(TRACE_DEBUG, "%s() called", __FUNCTION__);
 
   if(ntop_lua_check(vm, __FUNCTION__, 1, LUA_TNUMBER) != CONST_LUA_OK) return(CONST_LUA_ERROR);
-  id = (u_int32_t)lua_tonumber(vm, 1);
+  id = lua_tonumber(vm, 1);
 
   iface = ntop->getNetworkInterface(vm, id);
 
@@ -2569,6 +2569,17 @@ static int ntop_check_interface_alerts_day(lua_State* vm)  { return(ntop_check_i
 
 /* ****************************************** */
 
+static int ntop_check_snmp_device_alerts(lua_State* vm, ScriptPeriodicity p) {
+  ntop->checkSNMPDeviceAlerts(p);
+
+  lua_pushnil(vm);
+  return(CONST_LUA_OK);
+}
+
+static int ntop_check_snmp_device_alerts_5min(lua_State* vm)  { return(ntop_check_snmp_device_alerts(vm, five_minute_script)); }
+
+/* ****************************************** */
+
 static int ntop_temporary_disable_alerts(lua_State* vm) {
   bool to_disable;
   if(!ntop->isUserAdministrator(vm)) return(CONST_LUA_ERROR);
@@ -11321,6 +11332,9 @@ static const luaL_Reg ntop_reg[] = {
   { "refreshDeviceProtocolsPoliciesConf", ntop_refresh_device_protocols_policies_pref },
 #endif
 
+  /* Alerts */
+  { "checkSNMPDeviceAlerts5Min", ntop_check_snmp_device_alerts_5min },
+
   { NULL,          NULL}
 };
 
diff --git a/src/Ntop.cpp b/src/Ntop.cpp
index 4acb850b6d..36a0206957 100644
--- a/src/Ntop.cpp
+++ b/src/Ntop.cpp
@@ -818,6 +818,17 @@ void Ntop::setCustomnDPIProtos(char *path) {
   }
 }
 
+/* *************************************** */
+
+void Ntop::checkSNMPDeviceAlerts(ScriptPeriodicity p) {
+  AlertCheckLuaEngine acle(alert_entity_snmp_device, p, NULL);
+  lua_State *L = acle.getState();
+
+  lua_getglobal(L,  ALERT_ENTITY_CALLBACK_CHECK_ALERTS); /* Called function */
+  lua_pushstring(L, acle.getGranularity());              /* push 1st argument */
+  acle.pcall(1 /* num args */, 0);
+}
+
 /* ******************************************* */
 
 void Ntop::lua_periodic_activities_stats(NetworkInterface *iface, lua_State* vm) {