diff --git a/confgenerator/confgenerator_test.go b/confgenerator/confgenerator_test.go
index 4f1dc10d..bf84fcb5 100644
--- a/confgenerator/confgenerator_test.go
+++ b/confgenerator/confgenerator_test.go
@@ -103,7 +103,19 @@ func generateConfigs(testDir string) (got map[string]string, err error) {
 		}
 	}()
 
-	c, err := confgenerator.ReadConfigFromFile(ctx, filepath.Join("testdata", testDir, inputFileName))
+	portsEnv := ""
+	specEnv := ""
+	if strings.HasSuffix(testDir, "ports-env") {
+		portsEnv = "8080,9090,3030"
+	}
+	if strings.HasSuffix(testDir, "cfg-env") {
+		specEnv = `
+  endpoints:
+  - port: 8080
+    interval: 11s`
+	}
+
+	c, err := confgenerator.ReadConfigFromFile(ctx, filepath.Join("testdata", testDir, inputFileName), portsEnv, specEnv)
 	if err != nil {
 		return
 	}
diff --git a/confgenerator/config.go b/confgenerator/config.go
index c5ef09b3..019064e0 100644
--- a/confgenerator/config.go
+++ b/confgenerator/config.go
@@ -161,31 +161,52 @@ func DefaultRunMonitoringConfig() *RunMonitoringConfig {
 // ReadConfigFromFile reads the user config file and returns a RunMonitoringConfig.
 // If the user config file does not exist, or is empty - it returns the default
 // RunMonitoringConfig.
-func ReadConfigFromFile(ctx context.Context, path string) (*RunMonitoringConfig, error) {
+func ReadConfigFromFile(ctx context.Context, path string, scrapePorts, cfgEnv string) (*RunMonitoringConfig, error) {
 	config := DefaultRunMonitoringConfig()
 
 	// Fetch metadata from the available environment variables.
 	config.Env = fetchMetadata()
 
+	cfgFromEnv := false
 	if _, err := os.Stat(path); err != nil {
 		if os.IsNotExist(err) {
-			log.Println("confgenerator: no user config file found, using default config")
-			return config, nil
+			if cfgEnv != "" {
+				if err := yaml.UnmarshalContext(ctx, []byte(cfgEnv), &config.Spec, yaml.Strict()); err != nil {
+					return nil, err
+				}
+				cfgFromEnv = true
+			} else {
+				if scrapePorts != "" {
+					pl := strings.Split(scrapePorts, ",")
+					for _, p := range pl {
+						config.Spec.Endpoints = append(config.Spec.Endpoints, ScrapeEndpoint{
+							Port:     p,
+							Path:     "/metrics",
+							Interval: "30s"})
+					}
+					cfgFromEnv = true
+				}
+
+			}
+		}
+		if !cfgFromEnv {
+			return nil, fmt.Errorf("failed to retrieve the user config file %q: %w", path, err)
 		}
-		return nil, fmt.Errorf("failed to retrieve the user config file %q: %w", path, err)
 	}
 
-	data, err := ioutil.ReadFile(path)
-	if err != nil {
-		return nil, err
-	}
-	log.Printf("confgenerator: using RunMonitoring config:\n%s", string(data))
+	if !cfgFromEnv {
+		data, err := ioutil.ReadFile(path)
+		if err != nil {
+			return nil, err
+		}
+		log.Printf("confgenerator: using RunMonitoring config:\n%s", string(data))
 
-	// Unmarshal the user config over the default config. If some options are unspecified
-	// the collector uses the default settings for those options. For example, if not specified
-	// targetLabels is set to {"revision", "service", "configuration"}
-	if err := yaml.UnmarshalContext(ctx, data, config, yaml.Strict()); err != nil {
-		return nil, err
+		// Unmarshal the user config over the default config. If some options are unspecified
+		// the collector uses the default settings for those options. For example, if not specified
+		// targetLabels is set to {"revision", "service", "configuration"}
+		if err := yaml.UnmarshalContext(ctx, data, config, yaml.Strict()); err != nil {
+			return nil, err
+		}
 	}
 
 	// Validate the RunMonitoring config
diff --git a/confgenerator/testdata/cfg-env/golden/otel.yaml b/confgenerator/testdata/cfg-env/golden/otel.yaml
new file mode 100644
index 00000000..94192667
--- /dev/null
+++ b/confgenerator/testdata/cfg-env/golden/otel.yaml
@@ -0,0 +1,176 @@
+exporters:
+  googlemanagedprometheus:
+    metric:
+      add_metric_suffixes: false
+    untyped_double_export: true
+    user_agent: Google-Cloud-Run-GMP-Sidecar/latest; ShortName=run-gmp;ShortVersion=latest
+processors:
+  filter/run-gmp-self-metrics_0:
+    metrics:
+      include:
+        match_type: strict
+        metric_names:
+        - otelcol_process_uptime
+        - otelcol_process_memory_rss
+        - otelcol_grpc_io_client_completed_rpcs
+        - otelcol_googlecloudmonitoring_point_count
+  groupbyattrs/application-metrics_3:
+    keys:
+    - namespace
+    - cluster
+  groupbyattrs/run-gmp-self-metrics_4:
+    keys:
+    - namespace
+    - cluster
+  metricstransform/run-gmp-self-metrics_1:
+    transforms:
+    - action: update
+      include: otelcol_process_uptime
+      new_name: agent/uptime
+      operations:
+      - action: toggle_scalar_data_type
+      - action: add_label
+        new_label: version
+        new_value: run-gmp-sidecar@latest
+      - action: aggregate_labels
+        aggregation_type: sum
+        label_set:
+        - version
+    - action: update
+      include: otelcol_process_memory_rss
+      new_name: agent/memory_usage
+      operations:
+      - action: aggregate_labels
+        aggregation_type: sum
+        label_set: []
+    - action: update
+      include: otelcol_grpc_io_client_completed_rpcs
+      new_name: agent/api_request_count
+      operations:
+      - action: toggle_scalar_data_type
+      - action: update_label
+        label: grpc_client_status
+        new_label: state
+      - action: aggregate_labels
+        aggregation_type: sum
+        label_set:
+        - state
+    - action: update
+      include: otelcol_googlecloudmonitoring_point_count
+      new_name: agent/monitoring/point_count
+      operations:
+      - action: toggle_scalar_data_type
+      - action: aggregate_labels
+        aggregation_type: sum
+        label_set:
+        - status
+  resourcedetection/application-metrics_0:
+    detectors:
+    - gcp
+    - env
+  resourcedetection/run-gmp-self-metrics_2:
+    detectors:
+    - gcp
+    - env
+  transform/application-metrics_1:
+    metric_statements:
+      context: datapoint
+      statements:
+      - replace_pattern(resource.attributes["service.instance.id"], "^(\\d+)$$", Concat([resource.attributes["faas.id"],
+        "$$1"], ":"))
+  transform/application-metrics_2:
+    metric_statements:
+      context: datapoint
+      statements:
+      - set(attributes["instanceId"], resource.attributes["faas.id"])
+  transform/run-gmp-self-metrics_3:
+    metric_statements:
+      context: datapoint
+      statements:
+      - set(attributes["namespace"], "test_service")
+      - set(attributes["cluster"], "__run__")
+      - replace_pattern(resource.attributes["service.instance.id"], "^(\\d+)$$", Concat([resource.attributes["faas.id"],
+        "$$1"], ":"))
+receivers:
+  prometheus/application-metrics:
+    allow_cumulative_resets: true
+    config:
+      scrape_configs:
+      - job_name: run-gmp-sidecar
+        honor_timestamps: false
+        scrape_interval: 11s
+        scrape_timeout: 11s
+        metrics_path: /metrics
+        follow_redirects: false
+        enable_http2: false
+        relabel_configs:
+        - source_labels: [__address__]
+          target_label: service_name
+          replacement: test_service
+          action: replace
+        - source_labels: [__address__]
+          target_label: revision_name
+          replacement: test_revision
+          action: replace
+        - source_labels: [__address__]
+          target_label: configuration_name
+          replacement: test_configuration
+          action: replace
+        - source_labels: [__address__]
+          target_label: cluster
+          replacement: __run__
+          action: replace
+        - source_labels: [__address__]
+          target_label: namespace
+          replacement: test_service
+          action: replace
+        - source_labels: [__address__]
+          target_label: instance
+          replacement: "8080"
+          action: replace
+        static_configs:
+        - targets:
+          - 0.0.0.0:8080
+    preserve_untyped: true
+    use_collector_start_time_fallback: true
+    use_start_time_metric: true
+  prometheus/run-gmp-self-metrics:
+    config:
+      scrape_configs:
+      - job_name: run-gmp-sidecar-self-metrics
+        metric_relabel_configs:
+        - action: replace
+          replacement: "42"
+          source_labels:
+          - __address__
+          target_label: instance
+        scrape_interval: 1m
+        static_configs:
+        - targets:
+          - 0.0.0.0:42
+service:
+  pipelines:
+    metrics/application-metrics:
+      exporters:
+      - googlemanagedprometheus
+      processors:
+      - resourcedetection/application-metrics_0
+      - transform/application-metrics_1
+      - transform/application-metrics_2
+      - groupbyattrs/application-metrics_3
+      receivers:
+      - prometheus/application-metrics
+    metrics/run-gmp-self-metrics:
+      exporters:
+      - googlemanagedprometheus
+      processors:
+      - filter/run-gmp-self-metrics_0
+      - metricstransform/run-gmp-self-metrics_1
+      - resourcedetection/run-gmp-self-metrics_2
+      - transform/run-gmp-self-metrics_3
+      - groupbyattrs/run-gmp-self-metrics_4
+      receivers:
+      - prometheus/run-gmp-self-metrics
+  telemetry:
+    metrics:
+      address: 0.0.0.0:42
diff --git a/confgenerator/testdata/cfg-env/input.yaml.missing b/confgenerator/testdata/cfg-env/input.yaml.missing
new file mode 100644
index 00000000..867e2c84
--- /dev/null
+++ b/confgenerator/testdata/cfg-env/input.yaml.missing
@@ -0,0 +1 @@
+# Placeholder
\ No newline at end of file
diff --git a/confgenerator/testdata/ports-env/golden/otel.yaml b/confgenerator/testdata/ports-env/golden/otel.yaml
new file mode 100644
index 00000000..379a4559
--- /dev/null
+++ b/confgenerator/testdata/ports-env/golden/otel.yaml
@@ -0,0 +1,281 @@
+exporters:
+  googlemanagedprometheus:
+    metric:
+      add_metric_suffixes: false
+    untyped_double_export: true
+    user_agent: Google-Cloud-Run-GMP-Sidecar/latest; ShortName=run-gmp;ShortVersion=latest
+processors:
+  filter/run-gmp-self-metrics_0:
+    metrics:
+      include:
+        match_type: strict
+        metric_names:
+        - otelcol_process_uptime
+        - otelcol_process_memory_rss
+        - otelcol_grpc_io_client_completed_rpcs
+        - otelcol_googlecloudmonitoring_point_count
+  groupbyattrs/application-metrics_3:
+    keys:
+    - namespace
+    - cluster
+  groupbyattrs/run-gmp-self-metrics_4:
+    keys:
+    - namespace
+    - cluster
+  metricstransform/run-gmp-self-metrics_1:
+    transforms:
+    - action: update
+      include: otelcol_process_uptime
+      new_name: agent/uptime
+      operations:
+      - action: toggle_scalar_data_type
+      - action: add_label
+        new_label: version
+        new_value: run-gmp-sidecar@latest
+      - action: aggregate_labels
+        aggregation_type: sum
+        label_set:
+        - version
+    - action: update
+      include: otelcol_process_memory_rss
+      new_name: agent/memory_usage
+      operations:
+      - action: aggregate_labels
+        aggregation_type: sum
+        label_set: []
+    - action: update
+      include: otelcol_grpc_io_client_completed_rpcs
+      new_name: agent/api_request_count
+      operations:
+      - action: toggle_scalar_data_type
+      - action: update_label
+        label: grpc_client_status
+        new_label: state
+      - action: aggregate_labels
+        aggregation_type: sum
+        label_set:
+        - state
+    - action: update
+      include: otelcol_googlecloudmonitoring_point_count
+      new_name: agent/monitoring/point_count
+      operations:
+      - action: toggle_scalar_data_type
+      - action: aggregate_labels
+        aggregation_type: sum
+        label_set:
+        - status
+  resourcedetection/application-metrics_0:
+    detectors:
+    - gcp
+    - env
+  resourcedetection/run-gmp-self-metrics_2:
+    detectors:
+    - gcp
+    - env
+  transform/application-metrics_1:
+    metric_statements:
+      context: datapoint
+      statements:
+      - replace_pattern(resource.attributes["service.instance.id"], "^(\\d+)$$", Concat([resource.attributes["faas.id"],
+        "$$1"], ":"))
+  transform/application-metrics_2:
+    metric_statements:
+      context: datapoint
+      statements:
+      - set(attributes["instanceId"], resource.attributes["faas.id"])
+  transform/run-gmp-self-metrics_3:
+    metric_statements:
+      context: datapoint
+      statements:
+      - set(attributes["namespace"], "test_service")
+      - set(attributes["cluster"], "__run__")
+      - replace_pattern(resource.attributes["service.instance.id"], "^(\\d+)$$", Concat([resource.attributes["faas.id"],
+        "$$1"], ":"))
+receivers:
+  prometheus/application-metrics:
+    allow_cumulative_resets: true
+    config:
+      scrape_configs:
+      - job_name: run-gmp-sidecar
+        honor_timestamps: false
+        scrape_interval: 30s
+        scrape_timeout: 30s
+        metrics_path: /metrics
+        follow_redirects: false
+        enable_http2: false
+        relabel_configs:
+        - source_labels: [__address__]
+          target_label: service_name
+          replacement: test_service
+          action: replace
+        - source_labels: [__address__]
+          target_label: revision_name
+          replacement: test_revision
+          action: replace
+        - source_labels: [__address__]
+          target_label: configuration_name
+          replacement: test_configuration
+          action: replace
+        - source_labels: [__address__]
+          target_label: cluster
+          replacement: __run__
+          action: replace
+        - source_labels: [__address__]
+          target_label: namespace
+          replacement: test_service
+          action: replace
+        - source_labels: [__address__]
+          target_label: instance
+          replacement: "8080"
+          action: replace
+        static_configs:
+        - targets:
+          - 0.0.0.0:8080
+      - job_name: run-gmp-sidecar
+        honor_timestamps: false
+        scrape_interval: 30s
+        scrape_timeout: 30s
+        metrics_path: /metrics
+        follow_redirects: false
+        enable_http2: false
+        relabel_configs:
+        - source_labels: [__address__]
+          target_label: service_name
+          replacement: test_service
+          action: replace
+        - source_labels: [__address__]
+          target_label: revision_name
+          replacement: test_revision
+          action: replace
+        - source_labels: [__address__]
+          target_label: configuration_name
+          replacement: test_configuration
+          action: replace
+        - source_labels: [__address__]
+          target_label: cluster
+          replacement: __run__
+          action: replace
+        - source_labels: [__address__]
+          target_label: namespace
+          replacement: test_service
+          action: replace
+        - source_labels: [__address__]
+          target_label: instance
+          replacement: "8080"
+          action: replace
+        static_configs:
+        - targets:
+          - 0.0.0.0:8080
+      - job_name: run-gmp-sidecar
+        honor_timestamps: false
+        scrape_interval: 30s
+        scrape_timeout: 30s
+        metrics_path: /metrics
+        follow_redirects: false
+        enable_http2: false
+        relabel_configs:
+        - source_labels: [__address__]
+          target_label: service_name
+          replacement: test_service
+          action: replace
+        - source_labels: [__address__]
+          target_label: revision_name
+          replacement: test_revision
+          action: replace
+        - source_labels: [__address__]
+          target_label: configuration_name
+          replacement: test_configuration
+          action: replace
+        - source_labels: [__address__]
+          target_label: cluster
+          replacement: __run__
+          action: replace
+        - source_labels: [__address__]
+          target_label: namespace
+          replacement: test_service
+          action: replace
+        - source_labels: [__address__]
+          target_label: instance
+          replacement: "9090"
+          action: replace
+        static_configs:
+        - targets:
+          - 0.0.0.0:9090
+      - job_name: run-gmp-sidecar
+        honor_timestamps: false
+        scrape_interval: 30s
+        scrape_timeout: 30s
+        metrics_path: /metrics
+        follow_redirects: false
+        enable_http2: false
+        relabel_configs:
+        - source_labels: [__address__]
+          target_label: service_name
+          replacement: test_service
+          action: replace
+        - source_labels: [__address__]
+          target_label: revision_name
+          replacement: test_revision
+          action: replace
+        - source_labels: [__address__]
+          target_label: configuration_name
+          replacement: test_configuration
+          action: replace
+        - source_labels: [__address__]
+          target_label: cluster
+          replacement: __run__
+          action: replace
+        - source_labels: [__address__]
+          target_label: namespace
+          replacement: test_service
+          action: replace
+        - source_labels: [__address__]
+          target_label: instance
+          replacement: "3030"
+          action: replace
+        static_configs:
+        - targets:
+          - 0.0.0.0:3030
+    preserve_untyped: true
+    use_collector_start_time_fallback: true
+    use_start_time_metric: true
+  prometheus/run-gmp-self-metrics:
+    config:
+      scrape_configs:
+      - job_name: run-gmp-sidecar-self-metrics
+        metric_relabel_configs:
+        - action: replace
+          replacement: "42"
+          source_labels:
+          - __address__
+          target_label: instance
+        scrape_interval: 1m
+        static_configs:
+        - targets:
+          - 0.0.0.0:42
+service:
+  pipelines:
+    metrics/application-metrics:
+      exporters:
+      - googlemanagedprometheus
+      processors:
+      - resourcedetection/application-metrics_0
+      - transform/application-metrics_1
+      - transform/application-metrics_2
+      - groupbyattrs/application-metrics_3
+      receivers:
+      - prometheus/application-metrics
+    metrics/run-gmp-self-metrics:
+      exporters:
+      - googlemanagedprometheus
+      processors:
+      - filter/run-gmp-self-metrics_0
+      - metricstransform/run-gmp-self-metrics_1
+      - resourcedetection/run-gmp-self-metrics_2
+      - transform/run-gmp-self-metrics_3
+      - groupbyattrs/run-gmp-self-metrics_4
+      receivers:
+      - prometheus/run-gmp-self-metrics
+  telemetry:
+    metrics:
+      address: 0.0.0.0:42
diff --git a/confgenerator/testdata/ports-env/input.yaml.missing b/confgenerator/testdata/ports-env/input.yaml.missing
new file mode 100644
index 00000000..867e2c84
--- /dev/null
+++ b/confgenerator/testdata/ports-env/input.yaml.missing
@@ -0,0 +1 @@
+# Placeholder
\ No newline at end of file
diff --git a/entrypoint.go b/entrypoint.go
index 4c6043ec..1b151323 100644
--- a/entrypoint.go
+++ b/entrypoint.go
@@ -31,7 +31,7 @@ import (
 // Create channel to listen for signals.
 var signalChan chan (os.Signal) = make(chan os.Signal, 1)
 var userConfigFile = "/etc/rungmp/config.yaml"
-var otelConfigFile = "/run/rungmp/otel.yaml"
+var otelConfigFile = "/tmp/rungmp/otel.yaml"
 var configRefreshInterval = 20 * time.Second
 var selfMetricsPort = 0
 
@@ -57,7 +57,7 @@ func getRawUserConfig(userConfigFile string) (string, error) {
 func generateOtelConfig(ctx context.Context, userConfigFile string) error {
 	// Pick up RunMonitoring configuration from mounted volume that is tied to
 	// secret manager.  Translate it from RunMonitoring to OTel.
-	c, err := confgenerator.ReadConfigFromFile(ctx, userConfigFile)
+	c, err := confgenerator.ReadConfigFromFile(ctx, userConfigFile, os.Getenv("GMP_CFG_SPEC"), os.Getenv("GMP_SCRAPE_PORTS"))
 	if err != nil {
 		log.Fatal(err)
 	}