管理适用于 Kubernetes 的 Redis Enterprise 数据库

本节介绍数据库控制器如何通过数据库自定义资源提供创建、管理和使用数据库的能力。

适用于 Kubernetes 的 Redis Enterprise

Redis Enterprise Database （REDB） 生命周期

Redis Enterprise 数据库 （REDB） 是使用自定义资源文件创建的。自定义资源定义 REDB 的大小、名称和其他规范。应用自定义资源文件时，将创建数据库。

Redis Enterprise for Kubernetes 中的数据库控制器：

  • 发现自定义资源
  • 确保 REDB 是在与 Redis Enterprise 集群 （REC） 相同的命名空间中创建的
  • 保持自定义资源与 REDB 之间的一致性

数据库控制器识别新的自定义资源并验证规范。 如果有效，控制器将 具有默认值的自定义资源，用于创建完整规范。然后，它使用此完整规范创建 数据库。

创建数据库后，Redis Enterprise 集群的服务绑定人员将使用相同的服务机制公开该数据库。 如果删除了数据库自定义资源，则数据库及其服务将从集群中删除。

灵活的部署选项

多个命名空间中的数据库可以由同一个 Operator 管理。要了解更多信息，请参阅管理多个命名空间中的数据库。

要了解有关设计多命名空间 Redis Enterprise 集群的更多信息，请参阅灵活的部署选项。

创建数据库

您的 Redis Enterprise 数据库自定义资源必须为kind: RedisEnterpriseDatabase并具有name和memorySize.所有其他值都是可选的，如果未指定，则为默认值。

  1. 创建一个包含数据库自定义资源的文件（在本例中为 mydb.yaml）。

    apiVersion: app.redislabs.com/v1alpha1
kind: RedisEnterpriseDatabase
metadata:
  name: mydb
spec:
  memorySize: 1GB

    To create a REDB in a different namespace from your REC, you need to specify the cluster with redisEnterpriseCluster in the spec section of your RedisEnterpriseDatabase custom resource.

    redisEnterpriseCluster:
  name: rec

  2. Apply the file in the namespace you want your database to be in.

    kubectl apply -f mydb.yaml

  3. Check the status of your database.

    kubectl get redb mydb -o jsonpath="{.status.status}"

    When the status is active, the database is ready to use.

Modify a database

The custom resource defines the properties of the database. To change the database, you can edit your original specification and apply the change or use kubectl edit.

To modify the database:

  1. Edit the definition:

    kubectl edit redb mydb

  2. Change the specification (only properties in spec section) and save the changes.
    For more details, see RedisEnterpriseDatabaseSpec or Options for Redis Enterprise databases.

  3. Monitor the status to see when the changes take effect:

    kubectl get redb mydb -o jsonpath="{.status.status}"

    When the status is active, the database is ready for use.

Delete a database

The database exists as long as the custom resource exists. If you delete the custom resource, the database controller deletes the database. The database controller removes the database and its services from the cluster.

To delete a database, run:

kubectl delete redb mydb

Connect to a database

After the database controller creates a database, the services for accessing the database are created in the same namespace. By default there are two services, one 'ClusterIP' service and one 'headless' service.
Connection information for the database is stored in a Kubernetes secret maintained by the database controller. This secret contains:

  • The database port (port)
  • A comma separated list of service names (service_names)
  • The database password for authenticating (password)

The name of that secret is stored in the database custom resource.

Note:
Use these steps to connect to your database from within your K8s cluster. To access your database from outside the K8s cluster, set up the Ingress controller or use OpenShift routes.

  1. Retrieve the secret name.

    kubectl get redb mydb -o jsonpath="{.spec.databaseSecretName}"

    The database secret name usually takes the form of redb-<database_name>, so in our example it will be redb-mydb.

  2. Retrieve and decode the password.

    kubectl get secret redb-mydb -o jsonpath="{.data.password}" | base64 --decode

  3. Retrieve and decode the port number.

    kubectl get secret redb-mydb -o jsonpath="{.data.port}" | base64 --decode

  4. Retrieve and decode the service_names.

    kubectl get secret redb-mydb -o jsonpath="{.data.service_names}" | base64 --decode

    You'll need to pick just one service listed here to use for connecting.

  5. From a pod within your cluster, use redis-cli to connect to your database.

    redis-cli -h <service_name> -p <port>

  6. Enter the password you retrieved from the secret.

    auth <password>

    You are now connected to your database!

RATE THIS PAGE
Back to top ↑