lib/promscrape/discovery/docker: support host networking mode

See https://github.com/prometheus/prometheus/issues/9116

docs/CHANGELOG.md

@@ -21,6 +21,7 @@ sort: 15
 * BUGFIX: vmselect: reset connection timeouts after each request to `vmstorage`. This should prevent from `cannot read data in 0.000 seconds: unexpected EOF` warning in logs. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1562). Thanks to @mxlxm .
 * BUGFIX: keep metric name for time series returned from [rollup_candlestick](https://docs.victoriametrics.com/MetricsQL.html#rollup_candlestick) function, since the returned series don't change the meaning of the original series. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1600).
 * BUGFIX: vmagent: properly use `https` scheme for wildcard TLS certificates for `role: ingress` targets in Kubernetes service discovery. See [this issue](https://github.com/prometheus/prometheus/issues/8902).
+* BUGFIX: vmagent: support host networking mode for `docker_sd_config`. See [this issue](https://github.com/prometheus/prometheus/issues/9116).
 
 
 ## [v1.65.0](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.65.0)

lib/promscrape/discovery/docker/api.go

@@ -13,8 +13,9 @@ import (
 var configMap = discoveryutils.NewConfigMap()
 
 type apiConfig struct {
-	client *discoveryutils.Client
+	client             *discoveryutils.Client
-	port   int
+	port               int
+	hostNetworkingHost string
 
 	// filtersQueryArg contains escaped `filters` query arg to add to each request to Docker Swarm API.
 	filtersQueryArg string
@@ -29,9 +30,14 @@ func getAPIConfig(sdc *SDConfig, baseDir string) (*apiConfig, error) {
 }
 
 func newAPIConfig(sdc *SDConfig, baseDir string) (*apiConfig, error) {
+	hostNetworkingHost := sdc.HostNetworkingHost
+	if hostNetworkingHost == "" {
+		hostNetworkingHost = "localhost"
+	}
 	cfg := &apiConfig{
-		port:            sdc.Port,
+		port:               sdc.Port,
-		filtersQueryArg: getFiltersQueryArg(sdc.Filters),
+		hostNetworkingHost: hostNetworkingHost,
+		filtersQueryArg:    getFiltersQueryArg(sdc.Filters),
 	}
 	if cfg.port == 0 {
 		cfg.port = 80

lib/promscrape/discovery/docker/container.go

@@ -39,7 +39,7 @@ func getContainersLabels(cfg *apiConfig) ([]map[string]string, error) {
 	if err != nil {
 		return nil, err
 	}
-	return addContainersLabels(containers, networkLabels, cfg.port), nil
+	return addContainersLabels(containers, networkLabels, cfg.port, cfg.hostNetworkingHost), nil
 }
 
 func getContainers(cfg *apiConfig) ([]container, error) {
@@ -58,7 +58,7 @@ func parseContainers(data []byte) ([]container, error) {
 	return containers, nil
 }
 
-func addContainersLabels(containers []container, networkLabels map[string]map[string]string, defaultPort int) []map[string]string {
+func addContainersLabels(containers []container, networkLabels map[string]map[string]string, defaultPort int, hostNetworkingHost string) []map[string]string {
 	var ms []map[string]string
 	for i := range containers {
 		c := &containers[i]
@@ -86,8 +86,12 @@ func addContainersLabels(containers []container, networkLabels map[string]map[st
 			}
 			if !added {
 				// Use fallback port when no exposed ports are available or if all are non-TCP
+				addr := hostNetworkingHost
+				if c.HostConfig.NetworkMode != "host" {
+					addr = discoveryutils.JoinHostPort(n.IPAddress, defaultPort)
+				}
 				m := map[string]string{
-					"__address__":              discoveryutils.JoinHostPort(n.IPAddress, defaultPort),
+					"__address__":              addr,
 					"__meta_docker_network_ip": n.IPAddress,
 				}
 				addCommonLabels(m, c, networkLabels[n.NetworkID])

lib/promscrape/discovery/docker/container_test.go

@@ -317,6 +317,118 @@ func Test_addContainerLabels(t *testing.T) {
 		want    []map[string]string
 		wantErr bool
 	}{
+		{
+			name: "NetworkMode!=host",
+			c: container{
+				ID:    "90bc3b31aa13da5c0b11af2e228d54b38428a84e25d4e249ae9e9c95e51a0700",
+				Names: []string{"/crow-server"},
+				Labels: map[string]string{
+					"com.docker.compose.config-hash":      "c9f0bd5bb31921f94cff367d819a30a0cc08d4399080897a6c5cd74b983156ec",
+					"com.docker.compose.container-number": "1",
+					"com.docker.compose.oneoff":           "False",
+					"com.docker.compose.project":          "crowserver",
+					"com.docker.compose.service":          "crow-server",
+					"com.docker.compose.version":          "1.11.2",
+				},
+				HostConfig: struct {
+					NetworkMode string
+				}{
+					NetworkMode: "bridge",
+				},
+				NetworkSettings: struct {
+					Networks map[string]struct {
+						IPAddress string
+						NetworkID string
+					}
+				}{
+					Networks: map[string]struct {
+						IPAddress string
+						NetworkID string
+					}{
+						"host": {
+							IPAddress: "172.17.0.2",
+							NetworkID: "1dd8d1a8bef59943345c7231d7ce8268333ff5a8c5b3c94881e6b4742b447634",
+						},
+					},
+				},
+			},
+			want: []map[string]string{
+				{
+					"__address__":                "172.17.0.2:8012",
+					"__meta_docker_container_id": "90bc3b31aa13da5c0b11af2e228d54b38428a84e25d4e249ae9e9c95e51a0700",
+					"__meta_docker_container_label_com_docker_compose_config_hash":      "c9f0bd5bb31921f94cff367d819a30a0cc08d4399080897a6c5cd74b983156ec",
+					"__meta_docker_container_label_com_docker_compose_container_number": "1",
+					"__meta_docker_container_label_com_docker_compose_oneoff":           "False",
+					"__meta_docker_container_label_com_docker_compose_project":          "crowserver",
+					"__meta_docker_container_label_com_docker_compose_service":          "crow-server",
+					"__meta_docker_container_label_com_docker_compose_version":          "1.11.2",
+					"__meta_docker_container_name":                                      "/crow-server",
+					"__meta_docker_container_network_mode":                              "bridge",
+					"__meta_docker_network_id":                                          "1dd8d1a8bef59943345c7231d7ce8268333ff5a8c5b3c94881e6b4742b447634",
+					"__meta_docker_network_ingress":                                     "false",
+					"__meta_docker_network_internal":                                    "false",
+					"__meta_docker_network_ip":                                          "172.17.0.2",
+					"__meta_docker_network_name":                                        "bridge",
+					"__meta_docker_network_scope":                                       "local",
+				},
+			},
+		},
+		{
+			name: "NetworkMode=host",
+			c: container{
+				ID:    "90bc3b31aa13da5c0b11af2e228d54b38428a84e25d4e249ae9e9c95e51a0700",
+				Names: []string{"/crow-server"},
+				Labels: map[string]string{
+					"com.docker.compose.config-hash":      "c9f0bd5bb31921f94cff367d819a30a0cc08d4399080897a6c5cd74b983156ec",
+					"com.docker.compose.container-number": "1",
+					"com.docker.compose.oneoff":           "False",
+					"com.docker.compose.project":          "crowserver",
+					"com.docker.compose.service":          "crow-server",
+					"com.docker.compose.version":          "1.11.2",
+				},
+				HostConfig: struct {
+					NetworkMode string
+				}{
+					NetworkMode: "host",
+				},
+				NetworkSettings: struct {
+					Networks map[string]struct {
+						IPAddress string
+						NetworkID string
+					}
+				}{
+					Networks: map[string]struct {
+						IPAddress string
+						NetworkID string
+					}{
+						"host": {
+							IPAddress: "172.17.0.2",
+							NetworkID: "1dd8d1a8bef59943345c7231d7ce8268333ff5a8c5b3c94881e6b4742b447634",
+						},
+					},
+				},
+			},
+			want: []map[string]string{
+				{
+					"__address__":                "foobar",
+					"__meta_docker_container_id": "90bc3b31aa13da5c0b11af2e228d54b38428a84e25d4e249ae9e9c95e51a0700",
+					"__meta_docker_container_label_com_docker_compose_config_hash":      "c9f0bd5bb31921f94cff367d819a30a0cc08d4399080897a6c5cd74b983156ec",
+					"__meta_docker_container_label_com_docker_compose_container_number": "1",
+					"__meta_docker_container_label_com_docker_compose_oneoff":           "False",
+					"__meta_docker_container_label_com_docker_compose_project":          "crowserver",
+					"__meta_docker_container_label_com_docker_compose_service":          "crow-server",
+					"__meta_docker_container_label_com_docker_compose_version":          "1.11.2",
+					"__meta_docker_container_name":                                      "/crow-server",
+					"__meta_docker_container_network_mode":                              "host",
+					"__meta_docker_network_id":                                          "1dd8d1a8bef59943345c7231d7ce8268333ff5a8c5b3c94881e6b4742b447634",
+					"__meta_docker_network_ingress":                                     "false",
+					"__meta_docker_network_internal":                                    "false",
+					"__meta_docker_network_ip":                                          "172.17.0.2",
+					"__meta_docker_network_name":                                        "bridge",
+					"__meta_docker_network_scope":                                       "local",
+				},
+			},
+		},
 		{
 			name: "get labels from a container",
 			c: container{
@@ -391,7 +503,7 @@ func Test_addContainerLabels(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			labelsMap := addContainersLabels([]container{tt.c}, networkLabels, 80)
+			labelsMap := addContainersLabels([]container{tt.c}, networkLabels, 8012, "foobar")
 			if (err != nil) != tt.wantErr {
 				t.Errorf("addContainersLabels() error = %v, wantErr %v", err, tt.wantErr)
 				return

lib/promscrape/discovery/docker/docker.go

@@ -18,9 +18,10 @@ var SDCheckInterval = flag.Duration("promscrape.dockerSDCheckInterval", 30*time.
 //
 // See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#docker_sd_config
 type SDConfig struct {
-	Host    string   `yaml:"host"`
+	Host               string   `yaml:"host"`
-	Port    int      `yaml:"port,omitempty"`
+	Port               int      `yaml:"port,omitempty"`
-	Filters []Filter `yaml:"filters,omitempty"`
+	Filters            []Filter `yaml:"filters,omitempty"`
+	HostNetworkingHost string   `yaml:"host_networking_host,omitempty"`
 
 	HTTPClientConfig  promauth.HTTPClientConfig  `yaml:",inline"`
 	ProxyURL          proxy.URL                  `yaml:"proxy_url,omitempty"`