v1 Endpoints deprecation warning persists in v1.13.0 for discovery.kubernetes / loki.source.kubernetes components

[omarhadary]

Component(s)

discovery.kubernetes

Add a description

Component(s)

• discovery.kubernetes
• loki.source.kubernetes
• loki.source.kubernetes_events

What's wrong?

After upgrading to Alloy v1.13.0, which fixed the same warning for otelcol.exporter.loadbalancing (#4621), the following warning still appears repeatedly in logs:

W0327 11:39:28.871763 1 warnings.go:70] v1 Endpoints is deprecated in v1.33+; use discovery.k8s.io/v1 EndpointSlice

Our configuration does not use otelcol.exporter.loadbalancing. The warning must be coming from one of the other components that internally call the Kubernetes v1 Endpoints API. Based on our config, the likely sources are discovery.kubernetes (role=pod), loki.source.kubernetes, or loki.source.kubernetes_events.

The Kubernetes Endpoints API was officially deprecated in Kubernetes v1.33 (blog post). While the warning is non-breaking, it floods the logs and signals that the underlying client code should migrate to discovery.k8s.io/v1 EndpointSlice.

Steps to reproduce

1. Deploy Alloy v1.13.0 on a Kubernetes v1.33+ cluster
2. Configure discovery.kubernetes with role = "pod" and loki.source.kubernetes (see config below)
3. Observe the deprecation warning in Alloy logs

System information

• Kubernetes v1.33+
• Alloy v1.13.0 (Helm chart v1.4.0)

Configuration

discovery.kubernetes "pods" {
  role = "pod"

  selectors {
    role  = "pod"
    field = "spec.nodeName=" + coalesce(sys.env("HOSTNAME"), constants.hostname)
  }
}

discovery.relabel "pods_lithium" {
  targets = discovery.kubernetes.pods.targets

  rule {
    source_labels = ["__meta_kubernetes_namespace"]
    regex         = "^lithium-.*"
    action        = "keep"
  }
}

prometheus.scrape "pods_lithium" {
  targets          = discovery.relabel.pods_lithium.output
  forward_to       = [prometheus.remote_write.default.receiver]
  honor_timestamps = false
}

loki.source.kubernetes "pods_lithium" {
  targets    = discovery.relabel.pods_lithium.output
  forward_to = [loki.process.filter_probes.receiver]
}

loki.source.kubernetes_events "cluster_events" {
  job_name   = "integrations/kubernetes/eventhandler"
  log_format = "logfmt"
  forward_to = [loki.process.events_labels.receiver]
}

otelcol.receiver.otlp "default" {
  grpc { endpoint = "0.0.0.0:4317" }
  http { endpoint = "0.0.0.0:4318" }
  output {
    traces = [otelcol.processor.batch.default.input]
  }
}

otelcol.processor.batch "default" {
  output {
    traces = [otelcol.exporter.otlp.default.input]
  }
}
Logs

W0327 11:39:28.871763       1 warnings.go:70] v1 Endpoints is deprecated in v1.33+; use discovery.k8s.io/v1 EndpointSlice
Related
#4621 — Fixed the same warning for otelcol.exporter.loadbalancing in v1.13.0
#5480 — Docs update noting Endpoints deprecation for discovery.kubernetes

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[rriverak]

it floods the logs to avoid that, we simply increased the LogLevel to Error until its fixed/updated.

[rafaelpissolatto]

Hello! I'm also experiencing this issue with prometheus.operator.servicemonitors, prometheus.operator.podmonitors, and prometheus.operator.scrapeconfigs components.

Environment:

Kubernetes: v1.33+
Alloy Operator: v0.3.2 and v0.5.3
Alloy: v1.12.0 and v1.15.0
Configuration:

logging {}
livedebugging {}
prometheus.remote_write {}
prometheus.operator.servicemonitors {}
prometheus.operator.podmonitors {}
prometheus.operator.scrapeconfigs {}
prometheus.exporter.self {}
mimir.rules.kubernetes {}

Logs (v1.12.0):

I0410 12:31:56.079548       1 warnings.go:110] "Warning: v1 Endpoints is deprecated in v1.33+; use discovery.k8s.io/v1 EndpointSlice"
I0410 12:31:57.893029       1 warnings.go:110] "Warning: v1 Endpoints is deprecated in v1.33+; use discovery.k8s.io/v1 EndpointSlice"
I0410 12:31:59.589630       1 warnings.go:110] "Warning: v1 Endpoints is deprecated in v1.33+; use discovery.k8s.io/v1 EndpointSlice"

Logs (v1.15.0):

I0410 14:42:30.635416       1 warnings.go:107] "Warning: v1 Endpoints is deprecated in v1.33+; use discovery.k8s.io/v1 EndpointSlice"
I0410 14:42:49.628651       1 warnings.go:107] "Warning: v1 Endpoints is deprecated in v1.33+; use discovery.k8s.io/v1 EndpointSlice"

The warnings are very frequent (multiple times per second in some cases) and cause significant log noise. To try to help, the issue persists in the latest v1.15.0 release as well

We will increase the logging level to error only to suppress this too