We are going to setup Prometheus <-> ClickHouse-operator integration in k8s environment.
This document assumes k8s cluster already setup and kubectl
has access to it.
We may have two starting points:
- Prometheus installation is available and we just need to gather
clickhouse-operator
metrics - Need to install Prometheus at first and integrate it with
clickhouse-operator
afterwards
In case we have Prometheus already setup, what we need is to specify clickhouse-operator
's HTTP endpoint where Prometheus can gather metrics from clickhouse-operator
.
Endpoint is a Service of type ClusterIP named as clickhouse-operator-metrics
It is located in the same namespace as clickhouse-operator
:
kubectl get service clickhouse-operator-metrics -n kube-system
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
clickhouse-operator-metrics ClusterIP 10.105.15.167 <none> 8888/TCP 95m
For debug purposes, we can port-forward it into our local OS as
kubectl --namespace=kube-system port-forward service/clickhouse-operator-metrics 8888
and access raw data with browser by navigating to http://localhost:8888/metrics
So, what we need in general, is to point Prometheus to gather data from:
http://<service/clickhouse-operator-metrics>:8888/metrics
In case we do not have Prometheus available, we can setup it directly into k8s and integrate with clickhouse-operator
We are going to setup and manage Prometheus with Prometheus Operator
We already have manifests available. We can either run create-prometheus.sh or setup the whole process by hands, in case we need to edit configuration.
- We'd like to setup all Prometheus-related components into dedicated
namespace
. Let's create it
kubectl create namespace prometheus
- Create CRD for prometheus-operator like kind:Prometheus, kind:PrometheusRule etc.
kubectl --namespace=prometheus apply -f https://raw.githubusercontent.com/coreos/prometheus-operator/master/example/prometheus-operator-crd/monitoring.coreos.com_prometheuses.yaml
kubectl --namespace=prometheus apply -f https://raw.githubusercontent.com/coreos/prometheus-operator/master/example/prometheus-operator-crd/monitoring.coreos.com_prometheusrules.yaml
kubectl --namespace=prometheus apply -f https://raw.githubusercontent.com/coreos/prometheus-operator/master/example/prometheus-operator-crd/monitoring.coreos.com_alertmanagers.yaml
kubectl --namespace=prometheus apply -f https://raw.githubusercontent.com/coreos/prometheus-operator/master/example/prometheus-operator-crd/monitoring.coreos.com_podmonitors.yaml
kubectl --namespace=prometheus apply -f https://raw.githubusercontent.com/coreos/prometheus-operator/master/example/prometheus-operator-crd/monitoring.coreos.com_servicemonitors.yaml
kubectl --namespace=prometheus apply -f https://raw.githubusercontent.com/coreos/prometheus-operator/master/example/prometheus-operator-crd/monitoring.coreos.com_thanosrulers.yaml
- Create RBAC settings for
prometheus-operator
kubectl --namespace=prometheus apply -f <( \
wget -qO- https://raw.githubusercontent.com/coreos/prometheus-operator/master/example/rbac/prometheus/prometheus-cluster-role-binding.yaml | \
sed "s/namespace: default/namespace: prometheus/" \
)
kubectl --namespace=prometheus apply -f https://raw.githubusercontent.com/coreos/prometheus-operator/master/example/rbac/prometheus/prometheus-cluster-role.yaml
kubectl --namespace=prometheus apply -f https://raw.githubusercontent.com/coreos/prometheus-operator/master/example/rbac/prometheus/prometheus-service-account.yaml
- Setup
prometheus-operator
into dedicated namespace
kubectl --namespace=prometheus apply -f <( \
wget -qO- https://raw.githubusercontent.com/coreos/prometheus-operator/master/bundle.yaml | \
sed "s/namespace: default/namespace: prometheus/" \
)
- Setup
prometheus
into dedicated namespace.prometheus-operator
would be used to createprometheus
instance
kubectl apply --namespace=prometheus -f <(wget -qO- https://raw.githubusercontent.com/Altinity/clickhouse-operator/master/deploy/prometheus/prometheus-template.yaml | PROMETHEUS_NAMESPACE=prometheus envsubst)
- Setup
alertmanager
slack webhook, look at https://api.slack.com/incoming-webhooks how to enable external webhooks in Slack API
export SLACK_WEBHOOK_URL=https://hooks.slack.com/services/XXXX/YYYYY/ZZZZZ
export SLACK_CHANNEL="#alerts-channel-name"
export PROMETHEUS_NAMESPACE=prometheus
export ALERT_MANAGER_EXTERNAL_URL=https://your.external-domain.for-alertmanger/
kubectl apply --namespace=prometheus -f <( \
wget -qO- https://raw.githubusercontent.com/Altinity/clickhouse-operator/master/deploy/prometheus/prometheus-alertmanager-template.yaml | \
envsubst \
)
- Setup
clickhouse-operator
alert rules forprometheus
kubectl apply --namespace=prometheus -f https://raw.githubusercontent.com/Altinity/clickhouse-operator/master/deploy/prometheus/prometheus-alert-rules.yaml
At this point Prometheus and AlertManager is up and running. What we need to do - setup integration with clickhouse-operator
- Point
prometheus
to gather metrics fromclickhouse-operator
kubectl apply --namespace=prometheus -f https://raw.githubusercontent.com/Altinity/clickhouse-operator/master/deploy/prometheus/prometheus-clickhouse-operator-service-monitor.yaml
Now we should have Prometheus gathering metrics from clickhouse-operator
. Let's check it out.
To get access to Prometheus. Port-forward Prometheus to localhost
as:
kubectl --namespace=prometheus port-forward service/prometheus 9090
and navigate browser to http://localhost:9090
Prometheus should appear.
To get access to Alert Manager. Port-forward Prometheus to localhost
as:
kubectl --namespace=prometheus port-forward service/alertmanager 9093
and navigate browser to http://localhost:9093/alerts
Alert Manager should appear.
We can check whether clickhouse-operator
is available at http://localhost:9090/targets
More Prometheus docs