GitLab has support for automatically detecting and monitoring the Kubernetes NGINX ingress controller. This is provided by leveraging the built in Prometheus metrics included in [version 0.9.0](https://github.com/kubernetes/ingress/blob/master/controllers/nginx/Changelog.md#09-beta1) and above of the ingress.
## Requirements
[Prometheus integration](../prometheus/index.md) must be active.
If you have deployed NGINX Ingress using GitLab's [Kubernetes cluster integration](../../clusters/index.md#installing-applications), it will [automatically be monitored](#about-managed-nginx-ingress-deployments) by Prometheus.
For other deployments, there is [some configuration](#manually-setting-up-nginx-ingress-for-prometheus-monitoring) required depending on your installation:
* NGINX Ingress should be version 0.9.0 or above, with metrics enabled
* NGINX Ingress should be annotated for Prometheus monitoring
* Prometheus should be configured to monitor annotated pods
### About managed NGINX Ingress deployments
NGINX Ingress is deployed into the `gitlab-managed-apps` namespace, using the [official Helm chart](https://github.com/kubernetes/charts/tree/master/stable/nginx-ingress). NGINX Ingress will be [externally reachable via the Load Balancer's IP](https://docs.gitlab.com/ce/user/project/clusters/index.html#getting-the-external-ip-address).
NGINX is configured for Prometheus monitoring, by setting:
*`enable-vts-status: "true"`, to export Prometheus metrics
*`prometheus.io/scrape: "true"`, to enable automatic discovery
*`prometheus.io/port: "10254"`, to specify the metrics port
When used in conjunction with the GitLab deployed Prometheus service, response metrics will be automatically collected.
### Manually setting up NGINX Ingress for Prometheus monitoring
Version 0.9.0 and above of [NGINX ingress](https://github.com/kubernetes/ingress/tree/master/controllers/nginx) 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 will start running on port 10254.
Next, the ingress needs to be annotated for Prometheus monitoring. Two new annotations need to be added:
Managing these settings depends on how NGINX ingress has been deployed. If you have deployed via the [official Helm chart](https://github.com/kubernetes/charts/tree/master/stable/nginx-ingress), metrics can be enabled with `controller.stats.enabled` along with the required annotations. Alternatively it is possible edit the NGINX ingress YML directly in the [Kubernetes dashboard](https://github.com/kubernetes/dashboard).
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 will search for metrics with appropriate labels. In this case, the `upstream` label must be of the form `<KUBE_NAMESPACE>-<CI_ENVIRONMENT_SLUG>-*`.
If you have used [Auto Deploy](https://docs.gitlab.com/ee/ci/autodeploy/index.html) to deploy your app, this format will be used automatically and metrics will be detected with no action on your part.