Make localhost for local pods configurable via operator flag.

cmd/operator/main.go

@@ -94,6 +94,7 @@ func init() {
 	flagset.Var(&cfg.CrdKinds, "crd-kinds", " - EXPERIMENTAL (could be removed in future releases) - customize CRD kind names")
 	flagset.BoolVar(&cfg.EnableValidation, "with-validation", true, "Include the validation spec in the CRD")
 	flagset.BoolVar(&cfg.DisableAutoUserGroup, "disable-auto-user-group", false, "Disables the Prometheus Operator setting the `runAsUser` and `fsGroup` fields in Pods.")
+	flagset.StringVar(&cfg.LocalHost, "localhost", "localhost", "EXPERIMENTAL (could be removed in future releases) - Host used to communicate between local services on a pod. Fixes issues where localhost resolves incorrectly.")
 	flagset.StringVar(&cfg.LogLevel, "log-level", logLevelInfo, fmt.Sprintf("Log level to use. Possible values: %s", strings.Join(availableLogLevels, ", ")))
 	flagset.StringVar(&cfg.LogFormat, "log-format", logFormatLogfmt, fmt.Sprintf("Log format to use. Possible values: %s", strings.Join(availableLogFormats, ", ")))
 	flagset.BoolVar(&cfg.ManageCRDs, "manage-crds", true, "Manage all CRDs with the Prometheus Operator.")

pkg/alertmanager/operator.go

@@ -69,6 +69,7 @@ type Operator struct {
 
 type Config struct {
 	Host                         string
+	LocalHost                    string
 	ConfigReloaderImage          string
 	AlertmanagerDefaultBaseImage string
 	Namespace                    string
@@ -110,6 +111,7 @@ func New(c prometheusoperator.Config, logger log.Logger) (*Operator, error) {
 		queue:     workqueue.NewNamedRateLimitingQueue(workqueue.DefaultControllerRateLimiter(), "alertmanager"),
 		config: Config{
 			Host:                         c.Host,
+			LocalHost:                    c.LocalHost,
 			ConfigReloaderImage:          c.ConfigReloaderImage,
 			AlertmanagerDefaultBaseImage: c.AlertmanagerDefaultBaseImage,
 			Namespace:                    c.Namespace,

pkg/alertmanager/statefulset.go

@@ -206,7 +206,7 @@ func makeStatefulSetSpec(a *monitoringv1.Alertmanager, config Config) (*appsv1.S
 
 	localReloadURL := &url.URL{
 		Scheme: "http",
-		Host:   "localhost:9093",
+		Host:   config.LocalHost + ":9093",
 		Path:   path.Clean(webRoutePrefix + "/-/reload"),
 	}
 

pkg/prometheus/operator.go

@@ -135,6 +135,7 @@ type Config struct {
 	CrdKinds                     monitoringv1.CrdKinds
 	EnableValidation             bool
 	DisableAutoUserGroup         bool
+	LocalHost                    string
 	LogLevel                     string
 	LogFormat                    string
 	ManageCRDs                   bool

pkg/prometheus/statefulset.go

@@ -398,7 +398,7 @@ func makeStatefulSetSpec(p monitoringv1.Prometheus, c *Config, ruleConfigMapName
 
 	localReloadURL := &url.URL{
 		Scheme: "http",
-		Host:   "localhost:9090",
+		Host:   c.LocalHost + ":9090",
 		Path:   path.Clean(webRoutePrefix + "/-/reload"),
 	}
 
@@ -602,6 +602,7 @@ func makeStatefulSetSpec(p monitoringv1.Prometheus, c *Config, ruleConfigMapName
 
 		thanosArgs := []string{"sidecar"}
 
+		thanosArgs = append(thanosArgs, fmt.Sprintf("--prometheus.url=http://%s:9090", c.LocalHost))
 		thanosArgs = append(thanosArgs, fmt.Sprintf("--tsdb.path=%s", storageDir))
 		if p.Spec.Thanos.Peers != nil {
 			thanosArgs = append(thanosArgs, fmt.Sprintf("--cluster.peers=%s", *p.Spec.Thanos.Peers))