Monitoring NGINX Ingress Controller

Introduced in GitLab 11.7.

GitLab has support for automatically detecting and monitoring the Kubernetes NGINX Ingress controller. This is provided by leveraging the built-in Prometheus metrics included with Kubernetes NGINX Ingress controller version 0.16.0 onward.

noteNGINX Ingress versions prior to 0.16.0 offer an included VTS Prometheus metrics exporter, which exports metrics different than the built-in metrics.

Requirements

Prometheus integration must be active.

Metrics supported

Name Query
Throughput (req/sec) sum(label_replace(rate(nginx_ingress_controller_requests{namespace="%{kube_namespace}",ingress=~".*%{ci_environment_slug}.*"}[2m]), "status_code", "${1}xx", "status", "(.)..")) by (status_code)
Latency (ms) sum(rate(nginx_ingress_controller_ingress_upstream_latency_seconds_sum{namespace="%{kube_namespace}",ingress=~".*%{ci_environment_slug}.*"}[2m])) / sum(rate(nginx_ingress_controller_ingress_upstream_latency_seconds_count{namespace="%{kube_namespace}",ingress=~".*%{ci_environment_slug}.*"}[2m])) * 1000
HTTP Error Rate (%) sum(rate(nginx_ingress_controller_requests{status=~"5.*",namespace="%{kube_namespace}",ingress=~".*%{ci_environment_slug}.*"}[2m])) / sum(rate(nginx_ingress_controller_requests{namespace="%{kube_namespace}",ingress=~".*%{ci_environment_slug}.*"}[2m])) * 100

Configuring NGINX Ingress monitoring

Version 0.9.0 and above of NGINX Ingress have built-in support for exporting Prometheus metrics. To enable, a ConfigMap setting must be passed: enable-vts-status: "true". Once enabled, a Prometheus metrics endpoint starts running on port 10254.

Next, the Ingress needs to be annotated for Prometheus monitoring. Two new annotations need to be added:

  • prometheus.io/scrape: "true"
  • prometheus.io/port: "10254"

Managing these settings depends on how NGINX Ingress has been deployed. If you have deployed via the official Helm chart, metrics can be enabled with controller.stats.enabled along with the required annotations. Alternatively it is possible to edit the NGINX Ingress YML directly in the Kubernetes dashboard.

Specifying the Environment label

In order to isolate and only display relevant metrics for a given environment, GitLab needs a method to detect which labels are associated. To do this, GitLab searches for metrics with appropriate labels. In this case, the ingress label must <CI_ENVIRONMENT_SLUG>.

If you have used Auto Deploy to deploy your app, this format is used automatically and metrics are detected with no action on your part.