[prometheusreceiver] metric datapoints attributed to two different ServiceMonitor jobs

[diranged]

Component(s)

receiver/prometheus

What happened?

Description

We're setting up a single collector pod in a StatefulSet configured to monitor "all the rest" of our OTEL components ... this collector is called the otel-collector-cluster-agent, and it uses the TargetAllocator to monitor for ServiceMonitor jobs that have specific labels. We currently have two different ServiceMonitors - one for collecting otelcol.* metrics from the collectors, and one for collecting opentelemtry_.* metrics from the Target Allocators.

We are seeing metrics reported from the TargetAllocator pods duplicated into DataPoints that refer to the right, and wrong ServiceMonitor:

Metric #14
Descriptor:
     -> Name: opentelemetry_allocator_targets
     -> Description: Number of targets discovered.
     -> Unit: 
     -> DataType: Gauge
NumberDataPoints #0
Data point attributes:
     -> container: Str(ta-container)
     -> endpoint: Str(targetallocation)
     -> job_name: Str(serviceMonitor/otel/otel-collector-collectors/0)  <<<< WRONG
     -> namespace: Str(otel)
     -> pod: Str(otel-collector-cluster-agent-targetallocator-bdf46447d-6stx7)
     -> service: Str(otel-collector-cluster-agent-targetallocator)
StartTimestamp: 1970-01-01 00:00:00 +0000 UTC
Timestamp: 2024-05-02 16:16:00.917 +0000 UTC
Value: 36.000000
NumberDataPoints #1
Data point attributes:
     -> container: Str(ta-container)
     -> endpoint: Str(targetallocation)
     -> job_name: Str(serviceMonitor/otel/otel-collector-target-allocators/0)   <<<< RIGHT
     -> namespace: Str(otel)
     -> pod: Str(otel-collector-cluster-agent-targetallocator-bdf46447d-6stx7)
     -> service: Str(otel-collector-cluster-agent-targetallocator)
StartTimestamp: 1970-01-01 00:00:00 +0000 UTC
Timestamp: 2024-05-02 16:16:00.917 +0000 UTC

When we delete the otel-collector-collectors ServiceMonitor, the behavior does not change... which is wild... however, if we delete the entire stack and namespace and then re-create it without the second ServiceMonitor, then the data is correct... until we create the second Service Monitor, then it goes bad again.

Steps to Reproduce

apiVersion: opentelemetry.io/v1alpha1
kind: OpenTelemetryCollector
metadata:
  name: otel-collector-cluster-agent
  namespace: otel
spec:
  args:
    feature-gates: +processor.resourcedetection.hostCPUSteppingAsString
  config: |-
    exporters:
      debug:
        sampling_initial: 15
        sampling_thereafter: 60
      debug/verbose:
        sampling_initial: 15
        sampling_thereafter: 60
        verbosity: detailed
    extensions:
      health_check:
        endpoint: 0.0.0.0:13133
      pprof:
        endpoint: :1777
    receivers:
      prometheus:
        config:
          scrape_configs: []
        report_extra_scrape_metrics: true
    service:
      extensions:
      - health_check
      - pprof
      pipelines:
        metrics/debug:
          exporters:
          - debug/verbose
          receivers:
          - prometheus
      telemetry:
        logs:
          level: 'info'
  deploymentUpdateStrategy: {}
  env:
    - name: KUBE_NODE_NAME
      valueFrom:
        fieldRef:
          apiVersion: v1
          fieldPath: spec.nodeName
    - name: OTEL_RESOURCE_ATTRIBUTES
      value: node.name=$(KUBE_NODE_NAME)
  image: otel/opentelemetry-collector-contrib:0.98.0
  ingress:
    route: {}
  livenessProbe:
    failureThreshold: 3
    initialDelaySeconds: 60
    periodSeconds: 30
  managementState: managed
  mode: statefulset
  nodeSelector:
    kubernetes.io/os: linux
  observability:
    metrics: {}
  podDisruptionBudget:
    maxUnavailable: 1
  priorityClassName: otel-collector
  replicas: 1
  resources:
    limits:
      memory: 4Gi
    requests:
      cpu: "1"
      memory: 2Gi
  targetAllocator:
    allocationStrategy: consistent-hashing
    enabled: true
    filterStrategy: relabel-config
    image: otel/target-allocator:0.100.0-beta@sha256:fdd7e7f5f8f3903a3de229132ac0cf98c8857b7bdaf3451a764f550f7b037c26
    observability:
      metrics: {}
    podDisruptionBudget:
      maxUnavailable: 1
    prometheusCR:
      enabled: true
      podMonitorSelector:
        monitoring.xx.com/isolated: otel-cluster-agent
      scrapeInterval: 1m0s
      serviceMonitorSelector:
        monitoring.xx.com/isolated: otel-cluster-agent
    replicas: 1
    resources:
      limits:
        memory: 1Gi
      requests:
        cpu: 100m
        memory: 256Mi
  updateStrategy: {}
  upgradeStrategy: automatic

apiVersion: monitoring.coreos.com/v1
kind: ServiceMonitor
metadata:
  labels:
    app.kubernetes.io/instance: otel-collector
    app.kubernetes.io/managed-by: Helm
    app.kubernetes.io/name: otel-collector
    app.kubernetes.io/version: ""
    monitoring.xx.com/isolated: otel-cluster-agent
  name: otel-collector-collectors
  namespace: otel
spec:
  endpoints:
  - interval: 15s
    metricRelabelings:
    - action: keep
      regex: otelcol.*
      sourceLabels:
      - __name__
    port: monitoring
    scrapeTimeout: 5s
  namespaceSelector:
    matchNames:
    - otel
  selector:
    matchLabels:
      app.kubernetes.io/component: opentelemetry-collector
      app.kubernetes.io/managed-by: opentelemetry-operator
      operator.opentelemetry.io/collector-monitoring-service: Exists
---
apiVersion: monitoring.coreos.com/v1
kind: ServiceMonitor
metadata:
  labels:
    app.kubernetes.io/instance: otel-collector
    app.kubernetes.io/managed-by: Helm
    app.kubernetes.io/name: otel-collector
    app.kubernetes.io/version: ""
    monitoring.xx.com/isolated: otel-cluster-agent
  name: otel-collector-target-allocators
  namespace: otel
spec:
  endpoints:
  - interval: 15s
    metricRelabelings:
    - action: keep
      regex: opentelemetry.*
      sourceLabels:
      - __name__
    port: targetallocation
    scrapeTimeout: 5s
  namespaceSelector:
    matchNames:
    - otel
  selector:
    matchLabels:
      app.kubernetes.io/component: opentelemetry-targetallocator
      app.kubernetes.io/managed-by: opentelemetry-operator

This creates a /scrape_configs that looks like this:

% curl --silent localhost:8080/scrape_configs | jq .
{
  "serviceMonitor/otel/otel-collector-collectors/0": {
    "enable_compression": true,
    "enable_http2": true,
    "follow_redirects": true,
    "honor_timestamps": true,
    "job_name": "serviceMonitor/otel/otel-collector-collectors/0",
    "kubernetes_sd_configs": [
      {
        "enable_http2": true,
        "follow_redirects": true,
        "kubeconfig_file": "",
        "namespaces": {
          "names": [
            "otel"
          ],
          "own_namespace": false
        },
        "role": "endpointslice"
      }
    ],
    "metric_relabel_configs": [
      {
        "action": "keep",
        "regex": "otelcol.*",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__name__"
        ]
      }
    ],
    "metrics_path": "/metrics",
    "relabel_configs": [
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "job"
        ],
        "target_label": "__tmp_prometheus_job_name"
      },
      {
        "action": "keep",
        "regex": "(opentelemetry-collector);true",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_service_label_app_kubernetes_io_component",
          "__meta_kubernetes_service_labelpresent_app_kubernetes_io_component"
        ]
      },
      {
        "action": "keep",
        "regex": "(opentelemetry-operator);true",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_service_label_app_kubernetes_io_managed_by",
          "__meta_kubernetes_service_labelpresent_app_kubernetes_io_managed_by"
        ]
      },
      {
        "action": "keep",
        "regex": "(Exists);true",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_service_label_operator_opentelemetry_io_collector_monitoring_service",
          "__meta_kubernetes_service_labelpresent_operator_opentelemetry_io_collector_monitoring_service"
        ]
      },
      {
        "action": "keep",
        "regex": "monitoring",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_endpointslice_port_name"
        ]
      },
      {
        "action": "replace",
        "regex": "Node;(.*)",
        "replacement": "${1}",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_endpointslice_address_target_kind",
          "__meta_kubernetes_endpointslice_address_target_name"
        ],
        "target_label": "node"
      },
      {
        "action": "replace",
        "regex": "Pod;(.*)",
        "replacement": "${1}",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_endpointslice_address_target_kind",
          "__meta_kubernetes_endpointslice_address_target_name"
        ],
        "target_label": "pod"
      },
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_namespace"
        ],
        "target_label": "namespace"
      },
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_service_name"
        ],
        "target_label": "service"
      },
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_pod_name"
        ],
        "target_label": "pod"
      },
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_pod_container_name"
        ],
        "target_label": "container"
      },
      {
        "action": "drop",
        "regex": "(Failed|Succeeded)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_pod_phase"
        ]
      },
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "${1}",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_service_name"
        ],
        "target_label": "job"
      },
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "monitoring",
        "separator": ";",
        "target_label": "endpoint"
      },
      {
        "action": "hashmod",
        "modulus": 1,
        "regex": "(.*)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__address__"
        ],
        "target_label": "__tmp_hash"
      },
      {
        "action": "keep",
        "regex": "$(SHARD)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__tmp_hash"
        ]
      }
    ],
    "scheme": "http",
    "scrape_interval": "15s",
    "scrape_protocols": [
      "OpenMetricsText1.0.0",
      "OpenMetricsText0.0.1",
      "PrometheusText0.0.4"
    ],
    "scrape_timeout": "5s",
    "track_timestamps_staleness": false
  },
  "serviceMonitor/otel/otel-collector-target-allocators/0": {
    "enable_compression": true,
    "enable_http2": true,
    "follow_redirects": true,
    "honor_timestamps": true,
    "job_name": "serviceMonitor/otel/otel-collector-target-allocators/0",
    "kubernetes_sd_configs": [
      {
        "enable_http2": true,
        "follow_redirects": true,
        "kubeconfig_file": "",
        "namespaces": {
          "names": [
            "otel"
          ],
          "own_namespace": false
        },
        "role": "endpointslice"
      }
    ],
    "metric_relabel_configs": [
      {
        "action": "keep",
        "regex": "opentelemetry.*",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__name__"
        ]
      }
    ],
    "metrics_path": "/metrics",
    "relabel_configs": [
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "job"
        ],
        "target_label": "__tmp_prometheus_job_name"
      },
      {
        "action": "keep",
        "regex": "(opentelemetry-targetallocator);true",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_service_label_app_kubernetes_io_component",
          "__meta_kubernetes_service_labelpresent_app_kubernetes_io_component"
        ]
      },
      {
        "action": "keep",
        "regex": "(opentelemetry-operator);true",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_service_label_app_kubernetes_io_managed_by",
          "__meta_kubernetes_service_labelpresent_app_kubernetes_io_managed_by"
        ]
      },
      {
        "action": "keep",
        "regex": "targetallocation",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_endpointslice_port_name"
        ]
      },
      {
        "action": "replace",
        "regex": "Node;(.*)",
        "replacement": "${1}",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_endpointslice_address_target_kind",
          "__meta_kubernetes_endpointslice_address_target_name"
        ],
        "target_label": "node"
      },
      {
        "action": "replace",
        "regex": "Pod;(.*)",
        "replacement": "${1}",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_endpointslice_address_target_kind",
          "__meta_kubernetes_endpointslice_address_target_name"
        ],
        "target_label": "pod"
      },
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_namespace"
        ],
        "target_label": "namespace"
      },
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_service_name"
        ],
        "target_label": "service"
      },
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_pod_name"
        ],
        "target_label": "pod"
      },
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_pod_container_name"
        ],
        "target_label": "container"
      },
      {
        "action": "drop",
        "regex": "(Failed|Succeeded)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_pod_phase"
        ]
      },
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "${1}",
        "separator": ";",
        "source_labels": [
          "__meta_kubernetes_service_name"
        ],
        "target_label": "job"
      },
      {
        "action": "replace",
        "regex": "(.*)",
        "replacement": "targetallocation",
        "separator": ";",
        "target_label": "endpoint"
      },
      {
        "action": "hashmod",
        "modulus": 1,
        "regex": "(.*)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__address__"
        ],
        "target_label": "__tmp_hash"
      },
      {
        "action": "keep",
        "regex": "$(SHARD)",
        "replacement": "$1",
        "separator": ";",
        "source_labels": [
          "__tmp_hash"
        ]
      }
    ],
    "scheme": "http",
    "scrape_interval": "15s",
    "scrape_protocols": [
      "OpenMetricsText1.0.0",
      "OpenMetricsText0.0.1",
      "PrometheusText0.0.4"
    ],
    "scrape_timeout": "5s",
    "track_timestamps_staleness": false
  }
}

Expected Result

We should see datapoints for opentelemetry_.* metrics that only come from the target allocator pods and are attributed once .. meaning, one DataPoint per target pod, and that's it:

Metric #14
Descriptor:
     -> Name: opentelemetry_allocator_targets
     -> Description: Number of targets discovered.
     -> Unit: 
     -> DataType: Gauge
Value: 36.000000
NumberDataPoints #0
Data point attributes:
     -> container: Str(ta-container)
     -> endpoint: Str(targetallocation)
     -> job_name: Str(serviceMonitor/otel/otel-collector-target-allocators/0)   <<<< RIGHT
     -> namespace: Str(otel)
     -> pod: Str(otel-collector-cluster-agent-targetallocator-bdf46447d-6stx7)
     -> service: Str(otel-collector-cluster-agent-targetallocator)
StartTimestamp: 1970-01-01 00:00:00 +0000 UTC
Timestamp: 2024-05-02 16:16:00.917 +0000 UTC

Collector version

0.98.0

Environment information

Environment

OS: BottleRocket 1.19.2

OpenTelemetry Collector configuration

No response

Log output

No response

Additional context

No response

[github-actions]

Pinging code owners:

• receiver/prometheus: @Aneurysm9 @dashpole

See Adding Labels via Comments if you do not have permissions to add labels yourself.

[dashpole]

It isn't clear if this is an issue with the target allocator, or with the prometheus receiver. I would recommend opening re-opening the issue with the opentelemetry-operator first, and re-opening this issue once you have a minimal reproduction case with just the opentelemetry collector

[diranged]

I opened open-telemetry/opentelemetry-operator#2922 - but I am hesitant to close this just yet as I am not sure this is an operator issue... the configs that are generated for the Prometheus Receiver look right to me... this looks to me like it's something going wrong in the prometheus receiver.

The data points imply that two different ServiceMonitors are scraping the same endpoint .. but when you look at the rendered scrape_configs they clearly are pointing at different endpoints.. yet the DataPoints list the same endpoint value. That says to me that something is happening inside the Prometheus receiver to duplicate the data.

[dashpole]

Can you reproduce the issue with just static_configs, and without the target allocator? Then we can help here

[github-actions]

This issue has been inactive for 60 days. It will be closed in 60 days if there is no activity. To ping code owners by adding a component label, see Adding Labels via Comments, or if you are unsure of which component this issue relates to, please ping @open-telemetry/collector-contrib-triagers. If this issue is still relevant, please ping the code owners or leave a comment explaining why it is still relevant. Otherwise, please close it.

Pinging code owners:

• receiver/prometheus: @Aneurysm9 @dashpole

See Adding Labels via Comments if you do not have permissions to add labels yourself.