Note

ScalarDB Server is now deprecated. Please use ScalarDB Cluster instead.

This document explains how to create your custom values file for the ScalarDB Server chart. If you want to know the details of the parameters, please refer to the README of the ScalarDB Server chart.

Required configurations

Scalar Envoy configurations

You must set the Scalar Envoy configurations in the custom values file for ScalarDB Server. This is because client requests are sent to ScalarDB Server via Scalar Envoy as the load balancer of gRPC requests if you deploy ScalarDB Server on a Kubernetes environment.

Please refer to the document Configure a custom values file for Scalar Envoy for more details on the Scalar Envoy configurations.

envoy:
  configurationsForScalarEnvoy: 
    ...

scalardb:
  configurationsForScalarDB: 
    ...

Image configurations

You must set scalardb.image.repository. Be sure to specify the ScalarDB Server container image so that you can pull the image from the container repository.

scalardb:
  image:
    repository: <SCALARDB_SERVER_CONTAINER_IMAGE>

If you’re using AWS or Azure, please refer to the following documents for more details:

Database configurations

You must set scalardb.databaseProperties. Please set your database.properties to this parameter. Please refer to the Configure ScalarDB Server for more details on the configuration of ScalarDB Server.

scalardb:
  databaseProperties: |
    scalar.db.server.port=60051
    scalar.db.server.prometheus_exporter_port=8080
    scalar.db.server.grpc.max_inbound_message_size=
    scalar.db.server.grpc.max_inbound_metadata_size=
    scalar.db.contact_points=localhost
    scalar.db.username=cassandra
    scalar.db.password=cassandra
    scalar.db.storage=cassandra
    scalar.db.transaction_manager=consensus-commit
    scalar.db.consensus_commit.isolation_level=SNAPSHOT
    scalar.db.consensus_commit.serializable_strategy=
    scalar.db.consensus_commit.include_metadata.enabled=false

Optional configurations

If you want to control pod resources using the requests and limits of Kubernetes, you can use scalardb.resources.

Note that the resources for one pod of Scalar products are limited to 2vCPU / 4GB memory from the perspective of the commercial license. Also, when you get the pay-as-you-go containers provided from AWS Marketplace, you cannot run those containers with more than 2vCPU / 4GB memory configuration in the resources.limits. When you exceed this limitation, pods are automatically stopped.

You can configure them using the same syntax as the requests and limits of Kubernetes. So, please refer to the official document Resource Management for Pods and Containers for more details on the requests and limits of Kubernetes.

scalardb:
  resources:
    requests:
      cpu: 2000m
      memory: 4Gi
    limits:
      cpu: 2000m
      memory: 4Gi

If you want to use environment variables to set some properties (e.g., credentials) in the scalardb.databaseProperties, you can use scalardb.secretName to specify the Secret resource that includes some credentials.

For example, you can set credentials for a backend database (scalar.db.username and scalar.db.password) using environment variables, which makes your pods more secure.

Please refer to the document How to use Secret resources to pass the credentials as the environment variables into the properties file for more details on how to use a Secret resource.

scalardb:
  secretName: "scalardb-credentials-secret"

If you want to control pod deployment using the affinity and anti-affinity of Kubernetes, you can use scalardb.affinity.

You can configure them using the same syntax as the affinity of Kubernetes. So, please refer to the official document Assigning Pods to Nodes for more details on the affinity configuration of Kubernetes.

scalardb:
  affinity:
    podAntiAffinity:
      preferredDuringSchedulingIgnoredDuringExecution:
        - podAffinityTerm:
            labelSelector:
              matchExpressions:
                - key: app.kubernetes.io/name
                  operator: In
                  values:
                    - scalardb
                - key: app.kubernetes.io/app
                  operator: In
                  values:
                    - scalardb
            topologyKey: kubernetes.io/hostname
          weight: 50

Prometheus/Grafana configurations (Recommended in the production environment)

If you want to monitor ScalarDB Server pods using kube-prometheus-stack, you can deploy a ConfigMap, a ServiceMonitor, and a PrometheusRule resource for kube-prometheus-stack using scalardb.grafanaDashboard.enabled, scalardb.serviceMonitor.enabled, and scalardb.prometheusRule.enabled.

scalardb:
  grafanaDashboard:
    enabled: true
    namespace: monitoring
  serviceMonitor:
    enabled: true
    namespace: monitoring
    interval: 15s
  prometheusRule:
    enabled: true
    namespace: monitoring

If you want to set SecurityContext and PodSecurityContext for ScalarDB Server pods, you can use scalardb.securityContext and scalardb.podSecurityContext.

You can configure them using the same syntax as SecurityContext and PodSecurityContext of Kubernetes. So, please refer to the official document Configure a Security Context for a Pod or Container for more details on the SecurityContext and PodSecurityContext configurations of Kubernetes.

scalardb:
  podSecurityContext:
    seccompProfile:
      type: RuntimeDefault
  securityContext:
    capabilities:
      drop:
        - ALL
    runAsNonRoot: true
    allowPrivilegeEscalation: false

Replica configurations (Optional based on your environment)

You can specify the number of replicas (pods) of ScalarDB Server using scalardb.replicaCount.

scalardb:
  replicaCount: 3

Logging configurations (Optional based on your environment)

If you want to change the log level of ScalarDB Server, you can use scalardb.storageConfiguration.dbLogLevel.

scalardb:
  storageConfiguration:
    dbLogLevel: INFO

Taint and toleration configurations (Optional based on your environment)

If you want to control pod deployment by using the taints and tolerations in Kubernetes, you can use scalardb.tolerations.

You can configure taints and tolerations by using the same syntax as the tolerations in Kubernetes. For details on configuring tolerations in Kubernetes, see the official Kubernetes documentation Taints and Tolerations.

scalardb:
  tolerations:
    - effect: NoSchedule
      key: scalar-labs.com/dedicated-node
      operator: Equal
      value: scalardb