Add allow-duplicate-cn command-line flag

README.md

@@ -24,6 +24,7 @@ GLOBAL OPTIONS:
    --web.root value                                 Root path to exporter endpoints (default: "/") [$OPENVPN_EXPORTER_WEB_ROOT]
    --status-file value                              The OpenVPN status file(s) to export (example test:./example/version1.status ) [$OPENVPN_EXPORTER_STATUS_FILE]
    --disable-client-metrics                         Disables per client (bytes_received, bytes_sent, connected_since) metrics (default: false) [$OPENVPN_EXPORTER_DISABLE_CLIENT_METRICS]
+   --allow-duplicate-cn                             Allow multiple connections with the same common name distinguished by the Peer ID (only works with version 2 and 3 status types) (default: false) [$OPENVPN_EXPORTER_ALLOW_DUPLICATE_CN]
    --enable-golang-metrics                          Enables golang and process metrics for the exporter)  (default: false) [$OPENVPN_EXPORTER_ENABLE_GOLANG_METRICS]
    --log.level value                                Only log messages with given severity (default: "info") [$OPENVPN_EXPORTER_LOG_LEVEL]
    --help, -h                                       Show help (default: false)

example/version2.status

@@ -2,7 +2,8 @@ TITLE,OpenVPN 2.4.4 x86_64-pc-linux-gnu [SSL (OpenSSL)] [LZO] [LZ4] [EPOLL] [PKC
 TIME,Thu Apr 30 13:55:44 2020,1588254944
 HEADER,CLIENT_LIST,Common Name,Real Address,Virtual Address,Virtual IPv6 Address,Bytes Received,Bytes Sent,Connected Since,Connected Since (time_t),Username,Client ID,Peer ID
 CLIENT_LIST,test@localhost,1.2.3.4:54190,10.80.0.65,,3860,3688,Thu Apr 30 13:55:38 2020,1588254938,test@localhost,0,0
-CLIENT_LIST,test1@localhost,1.2.3.5:51053,10.68.0.25,,3871,3924,Thu Apr 30 13:55:40 2020,1588254940,test1@localhost,1,1
+CLIENT_LIST,test@localhost,1.2.3.4:54190,10.80.0.65,,3860,3688,Thu Apr 30 13:55:38 2020,1588254938,test@localhost,1,1
+CLIENT_LIST,test1@localhost,1.2.3.5:51053,10.68.0.25,,3871,3924,Thu Apr 30 13:55:40 2020,1588254940,test1@localhost,2,2
 HEADER,ROUTING_TABLE,Virtual Address,Common Name,Real Address,Last Ref,Last Ref (time_t)
 ROUTING_TABLE,10.80.0.65,test@localhost,1.2.3.4:54190,Thu Apr 30 13:55:40 2020,1588254940
 ROUTING_TABLE,10.68.0.25,test1@localhost,1.2.3.5:51053,Thu Apr 30 13:55:42 2020,1588254942

example/version3.status

@@ -2,7 +2,8 @@ TITLE	OpenVPN 2.4.4 x86_64-pc-linux-gnu [SSL (OpenSSL)] [LZO] [LZ4] [EPOLL] [PKC
 TIME	Thu Apr 30 13:55:44 2020	1588254944
 HEADER	CLIENT_LIST	Common Name	Real Address	Virtual Address	Virtual IPv6 Address	Bytes Received	Bytes Sent	Connected Since	Connected Since (time_t)	Username	Client ID	Peer ID
 CLIENT_LIST	test@localhost	1.2.3.4:54190	10.80.0.65		3860	3688	Thu Apr 30 13:55:38 2020	1588254938	test@localhost	0	0
-CLIENT_LIST	test1@localhost	1.2.3.5:51053	10.68.0.25		3871	3924	Thu Apr 30 13:55:40 2020	1588254940	test1@localhost	1	1
+CLIENT_LIST	test@localhost	1.2.3.4:54190	10.80.0.65		3860	3688	Thu Apr 30 13:55:38 2020	1588254938	test@localhost	1	1
+CLIENT_LIST	test1@localhost	1.2.3.5:51053	10.68.0.25		3871	3924	Thu Apr 30 13:55:40 2020	1588254940	test1@localhost	2	2
 HEADER	ROUTING_TABLE	Virtual Address	Common Name	Real Address	Last Ref	Last Ref (time_t)
 ROUTING_TABLE	10.80.0.65	test@localhost	1.2.3.4:54190	Thu Apr 30 13:55:40 2020	1588254940
 ROUTING_TABLE	10.68.0.25	test1@localhost	1.2.3.5:51053	Thu Apr 30 13:55:42 2020	1588254942

pkg/collector/openvpn.go

@@ -4,6 +4,7 @@ import (
 	"github.com/go-kit/kit/log"
 	"github.com/go-kit/kit/log/level"
 	"github.com/prometheus/client_golang/prometheus"
+	"strconv"
 
 	"github.com/patrickjahns/openvpn_exporter/pkg/openvpn"
 )
@@ -12,6 +13,7 @@ import (
 type OpenVPNCollector struct {
 	logger                log.Logger
 	collectClientMetrics  bool
+	allowDuplicateCn      bool
 	OpenVPNServer         []OpenVPNServer
 	LastUpdated           *prometheus.Desc
 	ConnectedClients      *prometheus.Desc
@@ -31,11 +33,12 @@ type OpenVPNServer struct {
 }
 
 // NewOpenVPNCollector returns a new OpenVPNCollector
-func NewOpenVPNCollector(logger log.Logger, openVPNServer []OpenVPNServer, collectClientMetrics bool) *OpenVPNCollector {
+func NewOpenVPNCollector(logger log.Logger, openVPNServer []OpenVPNServer, collectClientMetrics bool, allowDuplicateCn bool) *OpenVPNCollector {
 	return &OpenVPNCollector{
 		logger:               logger,
 		OpenVPNServer:        openVPNServer,
 		collectClientMetrics: collectClientMetrics,
+		allowDuplicateCn:     allowDuplicateCn,
 
 		LastUpdated: prometheus.NewDesc(
 			prometheus.BuildFQName(namespace, "", "last_updated"),
@@ -58,19 +61,19 @@ func NewOpenVPNCollector(logger log.Logger, openVPNServer []OpenVPNServer, colle
 		BytesReceived: prometheus.NewDesc(
 			prometheus.BuildFQName(namespace, "", "bytes_received"),
 			"Amount of data received via the connection",
-			[]string{"server", "common_name"},
+			[]string{"server", "common_name", "unique_id"},
 			nil,
 		),
 		BytesSent: prometheus.NewDesc(
 			prometheus.BuildFQName(namespace, "", "bytes_sent"),
 			"Amount of data sent via the connection",
-			[]string{"server", "common_name"},
+			[]string{"server", "common_name", "unique_id"},
 			nil,
 		),
 		ConnectedSince: prometheus.NewDesc(
 			prometheus.BuildFQName(namespace, "", "connected_since"),
 			"Unixtimestamp when the connection was established",
-			[]string{"server", "common_name"},
+			[]string{"server", "common_name", "unique_id"},
 			nil,
 		),
 		ServerInfo: prometheus.NewDesc(
@@ -127,6 +130,7 @@ func (c *OpenVPNCollector) collect(ovpn OpenVPNServer, ch chan<- prometheus.Metr
 	}
 
 	connectedClients := 0
+	hasFacedZeroPeerId := false
 	var clientCommonNames []string
 	for _, client := range status.ClientList {
 		connectedClients++
@@ -141,30 +145,46 @@ func (c *OpenVPNCollector) collect(ovpn OpenVPNServer, ch chan<- prometheus.Metr
 				continue
 			}
 			if contains(clientCommonNames, client.CommonName) {
-				level.Warn(c.logger).Log(
-					"msg", "duplicate client common name in statusfile - duplicate metric dropped",
-					"commonName", client.CommonName,
-				)
-				continue
+				if !c.allowDuplicateCn {
+					level.Warn(c.logger).Log(
+						"msg", "duplicate client common name in statusfile - duplicate metric dropped (use --allow-duplicate-cn flag)",
+						"commonName", client.CommonName,
+					)
+					continue
+				}
+				if c.allowDuplicateCn && client.PeerID == -1 {
+					level.Warn(c.logger).Log(
+						"msg", "allow-duplicate-cn flag with a version 1 statusfile - duplicate metric dropped (use version 2 or 3)",
+						"commonName", client.CommonName,
+					)
+					continue
+				}
 			}
 			clientCommonNames = append(clientCommonNames, client.CommonName)
+			uniqueId := client.PeerID
+			if uniqueId == 0 { // In TCP mode, PeerID is always 0
+				if hasFacedZeroPeerId { // Use ClientID only if a 0 PeerID is matched twice (maybe it's the first item and we are in UDP mode)
+					uniqueId = -client.ClientID - 1 // ClientID starts at 0; But it may be duplicated with another 0 PeerID
+				}
+				hasFacedZeroPeerId = true
+			}
 			ch <- prometheus.MustNewConstMetric(
 				c.BytesReceived,
-				prometheus.GaugeValue,
+				prometheus.CounterValue,
 				client.BytesReceived,
-				ovpn.Name, client.CommonName,
+				ovpn.Name, client.CommonName, strconv.FormatInt(uniqueId, 10),
 			)
 			ch <- prometheus.MustNewConstMetric(
 				c.BytesSent,
-				prometheus.GaugeValue,
+				prometheus.CounterValue,
 				client.BytesSent,
-				ovpn.Name, client.CommonName,
+				ovpn.Name, client.CommonName, strconv.FormatInt(uniqueId, 10),
 			)
 			ch <- prometheus.MustNewConstMetric(
 				c.ConnectedSince,
 				prometheus.GaugeValue,
 				float64(client.ConnectedSince.Unix()),
-				ovpn.Name, client.CommonName,
+				ovpn.Name, client.CommonName, strconv.FormatInt(uniqueId, 10),
 			)
 		}
 	}

pkg/command/command.go

@@ -78,6 +78,12 @@ func Run() error {
 			Usage:   "Disables per client (bytes_received, bytes_sent, connected_since) metrics",
 			EnvVars: []string{"OPENVPN_EXPORTER_DISABLE_CLIENT_METRICS"},
 		},
+		&cli.BoolFlag{
+			Name:        "allow-duplicate-cn",
+			Usage:       "Allow multiple connections with the same common name distinguished by the Peer ID (only works with version 2 and 3 status types)",
+			EnvVars:     []string{"OPENVPN_EXPORTER_ALLOW_DUPLICATE_CN"},
+			Destination: &cfg.AllowDuplicateCN,
+		},
 		&cli.BoolFlag{
 			Name:        "enable-golang-metrics",
 			Value:       false,
@@ -145,6 +151,7 @@ func run(cfg *config.Config) error {
 		logger,
 		openVPServers,
 		cfg.StatusCollector.ExportClientMetrics,
+		cfg.AllowDuplicateCN,
 	))
 
 	http.Handle(cfg.Server.Path,

pkg/config/config.go

@@ -14,10 +14,11 @@ type Logs struct {
 
 // Config defines the general configuration object
 type Config struct {
-	Server          Server
-	Logs            Logs
-	StatusCollector StatusCollector
-	ExportGoMetrics bool
+	Server           Server
+	Logs             Logs
+	StatusCollector  StatusCollector
+	ExportGoMetrics  bool
+	AllowDuplicateCN bool
 }
 
 // StatusCollector contains configuration for the OpenVPN status collector

pkg/openvpn/parser.go

@@ -23,6 +23,8 @@ type Client struct {
 	BytesReceived  float64
 	BytesSent      float64
 	ConnectedSince time.Time
+	ClientID       int64
+	PeerID         int64
 }
 
 // ServerInfo reflects information that was collected about the server
@@ -114,6 +116,7 @@ func parseStatusV1(reader io.Reader) (*Status, error) {
 					BytesReceived:  bytesRec,
 					BytesSent:      bytesSent,
 					ConnectedSince: parseTime(fields[4]),
+					PeerID:         -1,
 				}
 				clients = append(clients, client)
 			}
@@ -142,12 +145,16 @@ func parseStatusV2AndV3(reader io.Reader, separator string) (*Status, error) {
 			bytesRec, _ := strconv.ParseFloat(fields[5], 64)
 			bytesSent, _ := strconv.ParseFloat(fields[6], 64)
 			connectedSinceInt, _ := strconv.ParseInt(fields[8], 10, 64)
+			clientIdInt, _ := strconv.ParseInt(fields[10], 10, 64)
+			peerIdInt, _ := strconv.ParseInt(fields[11], 10, 64)
 			client := Client{
 				CommonName:     fields[1],
 				RealAddress:    parseIP(fields[2]),
 				BytesReceived:  bytesRec,
 				BytesSent:      bytesSent,
 				ConnectedSince: time.Unix(connectedSinceInt, 0),
+				ClientID:       clientIdInt,
+				PeerID:         peerIdInt,
 			}
 			clients = append(clients, client)
 		} else if fields[0] == "GLOBAL_STATS" {