k8s-inventory-client

k8s-inventory-client

Kubernetes application that collects, exposes and optionally uploads inventory data.

It runs in a loop every COLLECT_INTERNAL and collects:

• Cluster information (versions, etc)
• Workload information (deployments, etc)
• Infrastructure information (cloud, region, zone, etc)
• Node information
• Storage information
• Secure Cloud Stack specific information (customer data, etc)
• Custom Resource information (CNI, specific operators)

For more information about what is collected, see k8s-inventory.

Running

Configure the client (see Configuration below) and run the executable. It doesn't take any command line options or arguments:

k8s-inventory-client

k8s-inventory-client will try to detect if it's running inside a kubernetes cluster. If not, it will try to configure a kubernetes client by using the credentials and default context from ~/.kube/config. This makes it possible to run the client outside of a cluster, e.g. for development purposes.

Pre-requisites

Secure Cloud Stack Information

While not strictly required, not gathering Secure Cloud Stack information kind of defeats the purpose of running the client at all.

Secure Cloud Stack Information is read from ConfigMap-objects.

These objects must be created in the netic-metadata-system Namespace:

• General cluster information uses the first ConfigMap matching the netic.dk/owned-by=operator label
• Tenant information uses all ConfigMaps matching the netic.dk/owned-by=tenant label

See dist/deployment/netic-metadata.yaml for examples.

Permissions

In order to collect the data, k8s-inventory-client needs permission to read a wide array of resources. See dist/deployment/k8s-inventory-client.yaml for a list of permissions.

Configuration

Configuration is done using environment variables:

Collection Intervals

COLLECT_INTERNAL takes a values that can be parsed by time.ParseDuration().

Log Formatter

LOG_FORMATTER can be set to one of:

• json
• text

Log Level

LOG_LEVEL can be set to one of:

• debug
• info
• warn
• error
• fatal
• panic

Deploying

If you use a Secure Cloud Stack cluster, chances are k8s-inventory-client is already deployed.

However, if you need to deploy it yourself, you will need to:

• Create the ConfigMaps mentioned above
• Create the Kubernetes resources:
  • ServiceAccount
  • ClusterRole
  • ClusterRoleBinding
  • Service
  • Deployment

See kustomization.yaml for a full example of deploying the client.

netic-metadata.yaml creates the ConfigMaps.

k8s-inventory-client.yaml creates the other resources.

Typical adjustments:

• Set the app.kubernetes.io/version label to match the image version
• Set the image tag to the version you want to deploy
• In the Deployment set environment variables accordingly
• If using another port, set the Service ports

Building

Use the supplied Makefile.

make build or make build2 builds the executable and places it in bin/k8s-inventory-client. build forces rebuilding of packages and also runs the linter. build2 does not.

make docker-build and make docker-push builds/tags/pushes the docker image.