COS Lite

Canonical Observability Stack Lite is designed for the Edge and is capable of running reliably with limited computing resources (around 8 GB of overall memory, including MicroK8s and the Juju controller, limited CPU power).


The charmed operators that make up COS are available as the pre-configured COS Lite bundle. COS Lite is made up of the following Juju charmed operators:

Additionally, there are charmed operators designed to work with COS to provide additional functionality:

  • The Prometheus Scrape Config charm allows you to tweak the scrape jobs resulting from relating a charmed operator exposing the /metrics endpoint with the Prometheus charmed operator.

  • The Prometheus Scrape Target charmed operator allows you to represent in a Juju model /metrics endpoints provided by software not managed by Juju, e.g., LXD or MaaS, so that the Prometheus charmed operator can scrape metrics from them.

  • The COS Proxy charmed operator is a machine charm designed to “translate” the relations supported by the previous iteration, LMA, to COS.

  • The COS Configuration provides a GitOps approach to manage Prometheus alerts, Loki alerts and Grafana dashboards that are specific to your Juju deployments, rather than any particular charm.

  • The Karma charmed operator runs for you on Kubernetes the Karma UI, which enables you to visualize alerts from various Alertmanager clusters, e.g., when you were to deploy many different COS on Edge computing on in different production environments, and wanted to keep a centralized overview.

  • The Grafana Agent charmed operator provides a way to fetch and forward telemetry and dashboards from remote workloads and send them over to the observability stack.

Hi @0x12b, all

i’ve deployed the cos-lite bundle (for k8s) on a juju-deployed k8s cluster. i see that now there is traefik application too, i guess in order to get prometheus/graphana exposed.

Do you have documentation or examples for it? i tried with juju expose commands but i think the hooks do not apply anything on k8s side.

thank you

Hi @patrizio-bassi,

Awesome to hear that you’re trying out the stack! You should be able to follow this guide for setting up traefik.

Best, Simon