Charmed Kubernetes includes the standard Kubernetes dashboard for monitoring your cluster. However, it is often advisable to have a monitoring solution which will run whether the cluster itself is running or not. It may also be useful to integrate monitoring into existing setups.
Prometheus is the recommended way to monitor your deployment - instructions are provided below. There are also instructions for setting up other monitoring solutions, or connecting to existing monitoring setups.
Monitoring with Prometheus, Grafana, and Telegraf
The recommended way to monitor your cluster is to use a combination of Prometheus, Grafana and Telegraf. These provide a dashboard from which you can monitor both machine-level and cluster-level metrics. See the quickstart guide for more details on installing Charmed Kubernetes.
You can install Charmed Kubernetes with monitoring using the Juju bundle along with the following overlay file (download it here):
applications: prometheus: series: bionic charm: cs:prometheus2 constraints: "mem=4G root-disk=16G" num_units: 1 grafana: charm: cs:grafana expose: true num_units: 1 telegraf: charm: cs:telegraf relations: - [prometheus:grafana-source, grafana:grafana-source] - [telegraf:prometheus-client, prometheus:target] - [kubernetes-master:juju-info, telegraf:juju-info] - [kubernetes-worker:juju-info, telegraf:juju-info] - [kubernetes-master:prometheus, prometheus:manual-jobs] - [kubernetes-master:grafana, grafana:dashboards]
To use this overlay with the Charmed Kubernetes bundle, specify it during deploy like this:
juju deploy charmed-kubernetes --overlay ~/path/monitoring-pgt-overlay.yaml
If you wish to add monitoring to an existing deployment, you can export a bundle of your current environment and then redeploy it on top of itself with the overlay:
juju export-bundle --filename mybundle.yaml juju deploy ./mybundle.yaml --overlay ~/path/monitoring-pgt-overlay.yaml
Retrieve credentials and login
To open the dashboard in your browser you will need to know the URL and login credentials for Grafana. These can be retrieved with the following command:
juju run-action --wait grafana/0 get-login-info
This will return the connection and login information, like the following:
unit-grafana-0: id: a74acea6-8be9-43c1-8f1c-b1bebe9f5153 results: url: http://10.4.23.162:3000 username: admin password: NYZVkNb3jbMMhWhx status: completed timing: completed: 2019-07-29 22:00:29 +0000 UTC enqueued: 2019-07-29 22:00:27 +0000 UTC started: 2019-07-29 22:00:28 +0000 UTC unit: grafana/0
With that, you can visit the URL and log in using the username and password.
Once logged in, check out the cluster metric dashboard by clicking the
drop-down box and selecting
Kubernetes Metrics (via Prometheus):
You can also check out the system metrics of the cluster by switching the drop-down box to `Node Metrics (via Telegraf):
The kube-state-metrics project is a useful addon for monitoring workloads and their statuses. This involves installing a pod and service into Kubernetes, pointing Prometheus at that endpoint for scraping, and then setting up Grafana to use this data.
Starting with Charmed Kubernetes 1.17,
are added, automatically, when
enable-metrics is set to
true on the
kubernetes-master charm. This is enabled by default. Enable
with the following command.
juju config kubernetes-master enable-metrics=true
Monitoring with Nagios
Nagios (https://www.nagios.org/) is widely used for monitoring networks, servers and applications. Using the Nagios Remote Plugin Executor (NRPE) on each node, it can monitor your cluster with machine-level detail.
To start, deploy the latest version of the Nagios and NRPE Juju charms:
juju deploy nagios --series=bionic juju deploy nrpe --series=bionic juju expose nagios
Connect Nagios to NRPE:
juju add-relation nagios nrpe
Now add relations to NRPE for all the applications you wish to monitor, for example kubernetes-master, kubernetes-worker, etcd, easyrsa, and kubeapi-load-balancer.
juju add-relation nrpe kubernetes-master juju add-relation nrpe kubernetes-worker juju add-relation nrpe etcd juju add-relation nrpe easyrsa juju add-relation nrpe kubeapi-load-balancer
To connect to the Nagios server, you will need its IP address:
juju status --format yaml nagios/0 | grep public-address
The default username is
nagiosadmin. The password is randomly generated at
install time, and can be retrieved by running:
juju ssh nagios/0 sudo cat /var/lib/juju/nagios.passwd
Using an existing Nagios service
If you already have an existing Nagios installation, the
nrpe charm can
be configured to work with it.
juju config nrpe export_nagios_definitions=true juju config nrpe nagios_master=<ip-address-of-nagios>
See the External Nagios section of the NRPE charm readme for more information.