You are looking at the documentation of a prior release. To read the documentation of the latest release, please
visit here.
New to KubeDB? Please start here.
Monitoring SingleStore Using Prometheus operator
Prometheus operator provides simple and Kubernetes native way to deploy and configure Prometheus server. This tutorial will show you how to use Prometheus operator to monitor SingleStore database deployed with KubeDB.
The following diagram shows how KubeDB Provisioner operator monitor SingleStore using Prometheus Operator. Open the image in a new tab to see the enlarged version.
Before You Begin
At first, you need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. If you do not already have a cluster, you can create one by using kind.
To learn how Prometheus monitoring works with KubeDB in general, please visit here.
To keep database resources isolated, this tutorial uses a separate namespace called
demothroughout this tutorial. Run the following command to prepare your cluster:$ kubectl create ns demo namespace/demo createdWe need a Prometheus operator instance running. If you don’t already have a running instance, deploy one following the docs from here.
If you already don’t have a Prometheus server running, deploy one following tutorial from here.
Note: YAML files used in this tutorial are stored in docs/guides/singlestore/monitoring/prometheus-operator/yamls folder in GitHub repository kubedb/docs.
Find out required labels for ServiceMonitor
We need to know the labels used to select ServiceMonitor by a Prometheus crd. We are going to provide these labels in spec.monitor.prometheus.labels field of SingleStore crd so that KubeDB creates ServiceMonitor object accordingly.
At first, let’s find out the available Prometheus server in our cluster.
$ kubectl get prometheus --all-namespaces
NAMESPACE NAME VERSION REPLICAS AGE
default prometheus 1 2m19s
If you don’t have any Prometheus server running in your cluster, deploy one following the guide specified in Before You Begin section.
Now, let’s view the YAML of the available Prometheus server prometheus in default namespace.
$ kubectl get prometheus -n default prometheus -o yaml
apiVersion: monitoring.coreos.com/v1
kind: Prometheus
metadata:
annotations:
kubectl.kubernetes.io/last-applied-configuration: |
{"apiVersion":"monitoring.coreos.com/v1","kind":"Prometheus","metadata":{"annotations":{},"labels":{"prometheus":"prometheus"},"name":"prometheus","namespace":"default"},"spec":{"replicas":1,"resources":{"requests":{"memory":"400Mi"}},"serviceAccountName":"prometheus","serviceMonitorNamespaceSelector":{"matchLabels":{"prometheus":"prometheus"}},"serviceMonitorSelector":{"matchLabels":{"release":"prometheus"}}}}
creationTimestamp: "2020-08-25T04:02:07Z"
generation: 1
labels:
prometheus: prometheus
...
manager: kubectl
operation: Update
time: "2020-08-25T04:02:07Z"
name: prometheus
namespace: default
resourceVersion: "2087"
selfLink: /apis/monitoring.coreos.com/v1/namespaces/default/prometheuses/prometheus
uid: 972a50cb-b751-418b-b2bc-e0ecc9232730
spec:
replicas: 1
resources:
requests:
memory: 400Mi
serviceAccountName: prometheus
serviceMonitorNamespaceSelector:
matchLabels:
prometheus: prometheus
serviceMonitorSelector:
matchLabels:
release: prometheus
spec.serviceMonitorSelectorfield specifies which ServiceMonitors should be included. The Above labelrelease: prometheusis used to selectServiceMonitorsby its selector. So, we are going to use this label inspec.monitor.prometheus.labelsfield of SingleStore crd.spec.serviceMonitorNamespaceSelectorfield specifies that theServiceMonitorscan be selected outside the Prometheus namespace by Prometheus using namespace selector. The Above labelprometheus: prometheusis used to select the namespace where theServiceMonitoris created.
Add Label to database namespace
KubeDB creates a ServiceMonitor in database namespace demo. We need to add label to demo namespace. Prometheus will select this namespace by using its spec.serviceMonitorNamespaceSelector field.
Let’s add label prometheus: prometheus to demo namespace,
$ kubectl patch namespace demo -p '{"metadata":{"labels": {"prometheus":"prometheus"}}}'
namespace/demo patched
Create SingleStore License Secret
We need SingleStore License to create SingleStore Database. So, Ensure that you have acquired a license and then simply pass the license by secret.
$ kubectl create secret generic -n demo license-secret \
--from-literal=username=license \
--from-literal=password='your-license-set-here'
secret/license-secret created
Deploy SingleStore with Monitoring Enabled
At first, let’s deploy an SingleStore database with monitoring enabled. Below is the SingleStore object that we are going to create.
apiVersion: kubedb.com/v1alpha2
kind: Singlestore
metadata:
name: prom-operator-sdb
namespace: demo
spec:
version: "8.7.10"
topology:
aggregator:
replicas: 2
podTemplate:
spec:
containers:
- name: singlestore
resources:
limits:
memory: "2Gi"
cpu: "600m"
requests:
memory: "2Gi"
cpu: "600m"
storage:
storageClassName: "standard"
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
leaf:
replicas: 2
podTemplate:
spec:
containers:
- name: singlestore
resources:
limits:
memory: "2Gi"
cpu: "600m"
requests:
memory: "2Gi"
cpu: "600m"
storage:
storageClassName: "standard"
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 10Gi
licenseSecret:
name: license-secret
storageType: Durable
deletionPolicy: WipeOut
monitor:
agent: prometheus.io/operator
prometheus:
serviceMonitor:
labels:
release: prometheus
interval: 10s
Here,
monitor.agent: prometheus.io/operatorindicates that we are going to monitor this server using Prometheus operator.monitor.prometheus.labelsspecifies that KubeDB should createServiceMonitorwith these labels.monitor.prometheus.intervalindicates that the Prometheus server should scrape metrics from this database with 10 seconds interval.
Let’s create the SingleStore object that we have shown above,
$ kubectl create -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/singlestore/monitoring/prometheus-operator/yamls/prom-operator-singlestore.yaml
singlestore.kubedb.com/prom-operator-sdb created
Now, wait for the database to go into Running state.
$ watch -n 3 kubectl get singlestore -n demo prom-operator-sdb
NAME TYPE VERSION STATUS AGE
prom-operator-sdb kubedb.com/v1alpha2 8.7.10 Ready 10m
KubeDB will create a separate stats service with name {SingleStore crd name}-stats for monitoring purpose.
$ kubectl get svc -n demo --selector="app.kubernetes.io/instance=prom-operator-sdb"
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
prom-operator-sdb ClusterIP 10.128.249.124 <none> 3306/TCP,8081/TCP 12m
prom-operator-sdb-pods ClusterIP None <none> 3306/TCP 12m
prom-operator-sdb-stats ClusterIP 10.128.25.236 <none> 9104/TCP 12m
Here, prom-operator-sdb-stats service has been created for monitoring purpose.
Let’s describe this stats service.
$ kubectl describe svc -n demo prom-operator-sdb-stats
Name: prom-operator-sdb-stats
Namespace: demo
Labels: app.kubernetes.io/component=database
app.kubernetes.io/instance=prom-operator-sdb
app.kubernetes.io/managed-by=kubedb.com
app.kubernetes.io/name=singlestores.kubedb.com
kubedb.com/role=stats
Annotations: monitoring.appscode.com/agent: prometheus.io/operator
Selector: app.kubernetes.io/instance=prom-operator-sdb,app.kubernetes.io/managed-by=kubedb.com,app.kubernetes.io/name=singlestores.kubedb.com
Type: ClusterIP
IP Family Policy: SingleStack
IP Families: IPv4
IP: 10.128.25.236
IPs: 10.128.25.236
Port: metrics 9104/TCP
TargetPort: metrics/TCP
Endpoints: 10.2.1.140:9104,10.2.1.141:9104
Session Affinity: None
Events: <none>
Notice the Labels and Port fields. ServiceMonitor will use these information to target its endpoints.
KubeDB will also create a ServiceMonitor crd in demo namespace that select the endpoints of prom-operator-sdb-stats service. Verify that the ServiceMonitor crd has been created.
$ kubectl get servicemonitor -n demo
NAME AGE
prom-operator-sdb-stats 32m
Let’s verify that the ServiceMonitor has the label that we had specified in spec.monitor section of SingleStore crd.
$ kubectl get servicemonitor -n demo prom-operator-sdb-stats -oyaml
apiVersion: monitoring.coreos.com/v1
kind: ServiceMonitor
metadata:
creationTimestamp: "2024-10-01T05:37:40Z"
generation: 1
labels:
app.kubernetes.io/component: database
app.kubernetes.io/instance: prom-operator-sdb
app.kubernetes.io/managed-by: kubedb.com
app.kubernetes.io/name: singlestores.kubedb.com
release: prometheus
name: prom-operator-sdb-stats
namespace: demo
ownerReferences:
- apiVersion: v1
blockOwnerDeletion: true
controller: true
kind: Service
name: prom-operator-sdb-stats
uid: 33802913-be0f-49ea-ac81-cf0136ed9fbc
resourceVersion: "98648"
uid: f26855f0-5f0e-45a6-8bf2-531d2a370377
spec:
endpoints:
- honorLabels: true
interval: 10s
path: /metrics
port: metrics
namespaceSelector:
matchNames:
- demo
selector:
matchLabels:
app.kubernetes.io/component: database
app.kubernetes.io/instance: prom-operator-sdb
app.kubernetes.io/managed-by: kubedb.com
app.kubernetes.io/name: singlestores.kubedb.com
kubedb.com/role: stats
Notice that the ServiceMonitor has label release: prometheus that we had specified in SingleStore crd.
Also notice that the ServiceMonitor has selector which match the labels we have seen in the prom-operator-sdb-stats service. It also, target the prom-http port that we have seen in the stats service.
Verify Monitoring Metrics
At first, let’s find out the respective Prometheus pod for prometheus Prometheus server.
$ kubectl get pod -n default -l=app=prometheus
NAME READY STATUS RESTARTS AGE
prometheus-prometheus-0 3/3 Running 1 121m
Prometheus server is listening to port 9090 of prometheus-prometheus-0 pod. We are going to use port forwarding to access Prometheus dashboard.
Run following command on a separate terminal to forward the port 9090 of prometheus-prometheus-0 pod,
$ kubectl port-forward -n default prometheus-prometheus-0 9090
Forwarding from 127.0.0.1:9090 -> 9090
Forwarding from [::1]:9090 -> 9090
Now, we can access the dashboard at localhost:9090. Open http://localhost:9090 in your browser. You should see prom-http endpoint of prom-operator-sdb-stats service as one of the targets.
Check the endpoint and service labels marked by red rectangle. It verifies that the target is our expected database. Now, you can view the collected metrics and create a graph from homepage of this Prometheus dashboard. You can also use this Prometheus server as data source for Grafana and create beautiful dashboard with collected metrics.
Cleaning up
To cleanup the Kubernetes resources created by this tutorial, run following commands
# cleanup database
kubectl delete -n demo sdb/prom-operator-sdb
# cleanup Prometheus resources if exist
kubectl delete -f https://raw.githubusercontent.com/appscode/third-party-tools/master/monitoring/prometheus/coreos-operator/artifacts/prometheus.yaml
kubectl delete -f https://raw.githubusercontent.com/appscode/third-party-tools/master/monitoring/prometheus/coreos-operator/artifacts/prometheus-rbac.yaml
# cleanup Prometheus operator resources if exist
kubectl delete -f https://raw.githubusercontent.com/prometheus-operator/prometheus-operator/release-0.41/bundle.yaml
# delete namespace
kubectl delete ns demo
Next Steps
- Monitor your SingleStore database with KubeDB using out-of-the-box builtin-Prometheus.
- Detail concepts of SingleStore object.
- Want to hack on KubeDB? Check our contribution guidelines.