Extended-monitoring module

The extended-monitoring module extends cluster monitoring capabilities with additional Prometheus exporters, which allow you to identify potential problems before they affect the operation of services.

Module features:

• Advanced metrics collection.
• Container image monitoring.
• Cluster events collection.
• Certificate control.

For more details about module configuration and usage examples, refer to the corresponding documentation section.

Module architecture

The Level 2 C4 architecture of the extended-monitoring module and its interactions with other components of Deckhouse Kubernetes Platform (DKP) are shown in the following diagrams.

Module components

The module consists of the following components:

1. Extended-monitoring-exporter: Prometheus exporter that collects and expounds metrics for free space and inodes on nodes, as well as for objects with a label extended-monitoring.deckhouse.io/enabled ="" in the namespace. For more details about configuration of extended-monitoring metrics, refer to the corresponding documentation section. The module also contains Prometheus rules, based on which the Prometheus generates alerts. This allows you to detect and diagnose incidents faster.

   It consists of the following containers:

   • extended-monitoring-exporter: Main container. This exporter is developed by Flant.
   • kube-rbac-proxy: Sidecar container with an authorization proxy based on Kubernetes RBAC, providing secure access to exporter metrics. It is an open source project.

2. Image-availability-exporter: Prometheus exporter that monitors container images of pods running in cluster. Image-availability-exporter adds metrics about unavailability of container images to registry for all types of workload (Deployments, StatefulSets, DaemonSets, CronJobs). The module also contains appropriate Prometheus rules, based on which the Prometheus generates alerts. This helps to find out in advance about possible problems with launching or updating pods.

   It consists of the following containers:

   • image-availability-exporter: Main container. This exporter is developed by Flant.
   • kube-rbac-proxy: Sidecar container providing authorized access to exporter metrics (described above).

3. Events-exporter: Prometheus exporter that collects Kubernetes events and displays them as metrics, which allow you to track the dynamics of changes and respond faster to incidents.

   It consists of the following containers:

   • events-exporter: Main container. This exporter is developed by Flant.
   • kube-rbac-proxy: Sidecar container providing authorized access to exporter metrics (described above).

4. X509-certificate-exporter: Prometheus exporter that provides certificate control:

   • Scans the cluster’s Secrets and generates metrics about the expiration of x509 certificates.
   • The module also contains appropriate Prometheus rules, based on which the Prometheus generates alerts. This allows you not to miss critical moments and update certificates on time, avoiding application downtime due to expired certificates.

   It consists of the following containers:

   • x509-certificate-exporter: Main container. It is an open source project;
   • kube-rbac-proxy: Sidecar container providing authorized access to exporter metrics (described above).

Module interactions

The module interacts with the following components:

1. Kube-apiserver:

   • Watches Kubernetes API resources.
   • Watches cluster events (Events resources).
   • Scans the cluster’s Secrets.
   • Authorizes requests for metrics.

2. Container registry: Checks availability of container images.

The following external components interact with the module:

1. Prometheus-main: Collects metrics from module exporters.

Additional resources

• Module extended-monitoring documentation