community-operator

MongoDB Community Kubernetes Operator Helm Chart

A Helm Chart for installing and upgrading the MongoDB Community Kubernetes Operator.

Prerequisites

If required, you can install the Custom Resource Definitions Helm Chart separately or as a dependency of this Chart.

If the community-operator-crds Helm chart has been installed already, or if you don't want to install the CRDs (because you have already installed them), then you need to pass --set community-operator-crds.enabled=false, when installing the Operator.

Installing Community Operator

You can install the MongoDB Community Operator easily with:

helm install community-operator mongodb/community-operator

This will install CRDs and Community Operator in the current namespace (default by default). You can pass a different namespace with:

helm install community-operator mongodb/community-operator --namespace mongodb [--create-namespace]

To install the Community Operator in a namespace called mongodb with the optional --create-namespace in case mongodb didn't exist yet.

Deploying a MongoDB Replica Set

The Community Operator will be watching for resources of type mongodbcommunity.mongodbcommunity.mongodb.com; you can quickly install a sample Mongo Database with:

kubectl apply -f https://raw.githubusercontent.com/mongodb/mongodb-kubernetes-operator/master/config/samples/mongodb.com_v1_mongodbcommunity_cr.yaml [--namespace mongodb]

• Note: Make sure you add the --namespace option when needed.
• Note 2: A new user will be created with a generic password. Make sure this is only used for testing purposes.

After a few minutes you will have a 3-member MongoDB Replica Set installed in your cluster, that you can check with:

$ kubectl get mdbc
NAME              PHASE     VERSION
example-mongodb   Running   4.2.6

Connecting to MongoDB from a Client Application

The Operator will create a Secret object, per user, created as part of the deployment of the MongoDB resource. Each Secret will contain a Connection String that can be mounted into a client application to connect to this MongoDB instance.

The name of this Secret object follows the convention¹:

• <mongodb-resource-name>-<database>-<username>.

In our example, the above kubectl apply command will create a MongoDB resource with name example-mongodb, with a user my-user on the Database admin. The resulting Secret will be named:

• example-mongodb-admin-my-user

This Secret object will contain the following attributes:

• connectionString.standard
• connectionString.standardSrv
• username
• password

A client application will be able to connect using the connectionString attributes or the username and password ones.

Footnotes

1. Please note that the MongoDB username should comply with DNS-1123 for the Operator to be able to create this Secret. This is a known issue with the Community Operator. ↩