Added config flag to skip collection of network protocol metrics (#3880)

plugins/inputs/system/NET_README.md

@@ -14,6 +14,11 @@ This plugin gathers metrics about network interface and protocol usage (Linux on
   ##
   # interfaces = ["eth*", "enp0s[0-1]", "lo"]
   ##
+  ## On linux systems telegraf also collects protocol stats.
+  ## Setting ignore_protocol_stats to true will skip reporting of protocol metrics.
+  ##
+  # ignore_protocol_stats = false
+  ##
 ```
 
 ### Measurements & Fields:

plugins/inputs/system/net.go

@@ -15,6 +15,7 @@ type NetIOStats struct {
 	ps     PS
 
 	skipChecks          bool
+	IgnoreProtocolStats bool
 	Interfaces          []string
 }
 
@@ -28,6 +29,12 @@ var netSampleConfig = `
   ## regardless of status.
   ##
   # interfaces = ["eth0"]
+  ##
+  ## On linux systems telegraf also collects protocol stats.
+  ## Setting ignore_protocol_stats to true will skip reporting of protocol metrics.
+  ##
+  # ignore_protocol_stats = false
+  ##
 `
 
 func (_ *NetIOStats) SampleConfig() string {
@@ -91,6 +98,7 @@ func (s *NetIOStats) Gather(acc telegraf.Accumulator) error {
 
 	// Get system wide stats for different network protocols
 	// (ignore these stats if the call fails)
+	if !s.IgnoreProtocolStats {
 		netprotos, _ := s.ps.NetProto()
 		fields := make(map[string]interface{})
 		for _, proto := range netprotos {
@@ -104,6 +112,7 @@ func (s *NetIOStats) Gather(acc telegraf.Accumulator) error {
 			"interface": "all",
 		}
 		acc.AddFields("net", fields, tags)
+	}
 
 	return nil
 }

plugins/inputs/system/net_test.go

@@ -106,4 +106,10 @@ func TestNetStats(t *testing.T) {
 		"udp_socket":      1,
 	}
 	acc.AssertContainsTaggedFields(t, "netstat", fields3, make(map[string]string))
+
+	acc.Metrics = nil
+	err = (&NetIOStats{ps: &mps, IgnoreProtocolStats: true}).Gather(&acc)
+	require.NoError(t, err)
+
+	acc.AssertDoesNotContainsTaggedFields(t, "netstat", fields3, make(map[string]string))
 }