Nutanix Database Service Operator for Kubernetes

The NDB operator brings automated and simplified database administration, provisioning, and life-cycle management to Kubernetes.

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Getting Started

Pre-requisites

1. NDB installation.
2. A Kubernetes cluster to run against, which should have network connectivity to the NDB installation. You can use KIND to get a local cluster for testing, or run against a remote cluster. Note: The operator will automatically use the current context in your kubeconfig file (i.e. whatever cluster kubectl cluster-info shows).
3. The operator-sdk installed.
4. A clone of the source code (this repository).

Installation and Running on the cluster

Deploy the controller on the cluster:

make deploy 

Using the Operator

1. Create file "secrets.yaml" to store the secrets that can be used by the custom resources:

apiVersion: v1
kind: Secret
metadata:
  name: ndb-secret-name
type: Opaque
stringData:
  username: username-for-ndb-server
  password: password-for-ndb-server
  ca_certificate: |
    -----BEGIN CERTIFICATE-----
    CA CERTIFICATE (ca_certificate is optional)
    -----END CERTIFICATE-----
---
apiVersion: v1
kind: Secret
metadata:
  name: db-instance-secret-name
type: Opaque
stringData:
  password: password-for-the-database-instance
  ssh_public_key: SSH-PUBLIC-KEY

Apply the secrets:

kubectl apply -f <path/to/secrets.yaml>

You can optionally verify that they have been created:

kubectl get secrets

2. To create a Database CR, update these fields in the "spec" section of ndb_v1alpha1_database.yaml
   a. "server" : NDB Server IP
   b. "clusterId" : Nutanix Cluster Id
   c. "databaseInstanceName" : Database Instance Name

3. Finally, run this command to provision the database using NDB Operator:

kubectl apply -f config/samples/ndb_v1alpha1_database.yaml

4. To delete the Database CR (deprovision database) run:

kubectl delete -f config/samples/ndb_v1alpha1_database.yaml

The ndb_v1alpha1_database.yaml is described as follows:

apiVersion: ndb.nutanix.com/v1alpha1
kind: Database
metadata:
  # This name that will be used within the kubernetes cluster
  name: db
spec:
  # NDB server specific details
  ndb:
    # Cluster id of the cluster where the Database has to be provisioned
    # Can be fetched from the GET /clusters endpoint
    clusterId: "Nutanix Cluster Id" 
    # Credentials secret name for NDB installation
    # data: username, password, 
    # stringData: ca_certificate
    credentialSecret: ndb-secret-name
    # The NDB Server
    server: https://[NDB IP]:8443/era/v0.9
    # Set to true to skip SSL verification, default: false.
    skipCertificateVerification: true
  # Database instance specific details (that is to be provisioned)
  databaseInstance:
    # The database instance name on NDB
    databaseInstanceName: "Database-Instance-Name"
    # Names of the databases on that instance
    databaseNames:
      - database_one
      - database_two
      - database_three
    # Credentials secret name for NDB installation
    # data: password, ssh_public_key
    credentialSecret: db-instance-secret-name
    size: 10
    timezone: "UTC"
    type: postgres

Developement

Installation and Running the controller locally

1. Install the CRDs into the cluster:

make install

2. Run your controller locally (this will run in the foreground, so switch to a new terminal if you want to leave it running):

make run

NOTE: You can also run this in one step by running: make install run

Modifying the API definitions

If you are editing the API definitions, generate the manifests such as CRs or CRDs using:

make generate manifests

NOTE: Run make --help for more information on all potential make targets

More information can be found via the Kubebuilder Documentation

Building and pushing to an image registry

Build and push your image to the location specified by IMG:

make docker-build docker-push IMG=<some-registry>/ndb-operator:tag

Deploy the operator pushed to an image registry

Deploy the controller to the cluster with the image specified by IMG:

make deploy IMG=<some-registry>/ndb-operator:tag

Uninstall CRDs

To delete the CRDs from the cluster:

make uninstall

Undeploy controller

To remove the controller from the cluster:

make undeploy

How it works

This project aims to follow the Kubernetes Operator pattern

It uses Controllers which provides a reconcile function responsible for synchronizing resources until the desired state is reached on the cluster.

A custom resource of the kind Database is created by the reconciler, followed by a Service and an Endpoint that maps to the IP address of the database instance provisioned. Application pods/deployments can use this service to interact with the databases provisioned on NDB through the native Kubernetes service.

Pods can specify an initContainer to wait for the service (and hence the database instance) to get created before they start up.

  initContainers:
  - name: init-db
    image: busybox:1.28
    command: ['sh', '-c', "until nslookup <<Database CR Name>>-svc.$(cat /var/run/secrets/kubernetes.io/serviceaccount/namespace).svc.cluster.local; do echo waiting for database service; sleep 2; done"]

Contributing

See the contributing docs.

Support

Community Plus

This code is developed in the open with input from the community through issues and PRs. A Nutanix engineering team serves as the maintainer. Documentation is available in the project repository.

Issues and enhancement requests can be submitted in the Issues tab of this repository. Please search for and review the existing open issues before submitting a new issue.

License

Copyright 2021-2022 Nutanix, Inc.

The project is released under version 2.0 of the Apache license.