Production checklist

Even though the Helm Chart makes installing Stream a breeze, you’ll still have to set up a few things to make Stream resilient enough to operate in a production environment.

Operating the database

All persistent data used by Stream is stored in the underlying MongoDB database. Therefore, the database should be operated securely and backed up regularly.

When installing the chart, you face multiple options regarding your database:

By default, a local MongoDB standalone instance will be spawned in your cluster, using the bitnami/mongodb chart. No additional configuration is required but it is not production ready out of the box. You can configure the chart as you would normally below the mongodb key :
```
mongodb:
  architecture: replicaset
  # Any other YAML value from the chart docs
```
If you want to use an existing MongoDB instance, provide the externalDatabase.uri value. The URI should be treated as a secret as it must include credentials:
```
externalDatabase:
  secretName: <secret name>
  secretKey: <secret key>
```

The chart doesn’t manage the database. You are still in charge of making sure that the database is correctly backed up. You could either back up manually using mongodump or use a managed service such as MongoDB Atlas, which will take care of the backups for you.

Managing secrets

Storing secrets is a crucial part of your Stream installation. The keyset is the most import of them, being a master key used to encrypt and decrypt data before they enter the database. Alongside with other application secrets like your MongoDB URI (containing your credentials or certificate). We recommend that you create Kubernetes secrets beforehand or inject them directly into the pod.

Values that should be treated as secrets in this chart are:

Name Description Impact on loss

Name	Description	Impact on loss
`keyset`	Master key used to encrypt sensitive data in database.	Highest impact: database would be unusable
`events.secret`	Secret used to sign and chain events.	Moderate impact: events integrity would be unverifiable
`externalDatabase.uri`	External database URI, containing a username and password.	Low impact: reset the MongoDB password
`appSecret`	Application secret use to encrypt session data.	Low impact: sessions would be reset
`mailer.password`	SMTP server password	Low impact: reset the SMTP password

keyset

Master key used to encrypt sensitive data in database.

Highest impact: database would be unusable

events.secret

Secret used to sign and chain events.

Moderate impact: events integrity would be unverifiable

externalDatabase.uri

External database URI, containing a username and password.

Low impact: reset the MongoDB password

appSecret

Application secret use to encrypt session data.

Low impact: sessions would be reset

mailer.password

SMTP server password

Low impact: reset the SMTP password

For each of these values, either :

leave the field empty, so that a secret will be automatically generated.

derive the secret value from an existing Kubernetes secret:

appSecret:
  secretName: <secret name>
  secretKey: <secret key>

Always store secrets in a safe place after they’re generated. If you ever uninstall your Helm chart, the loss of the keyset will lead to the impossibility of recovering most of your data.

High availability

By default, the chart will configure a single-pod deployment. This deployment method is fine for testing but not ready for production as a single failure could take down the entire application. Instead, we recommend that you set up a Stream cluster using at least 3 pods.

In order to do that, configure an horizontalAutoscaler in your override-values.yaml file:

horizontalAutoscaler:
  enabled: true
  minReplicas: 3
  maxReplicas: 3

Use nodeAffinity to spread your Stream cluster Pods among multiple nodes in different availability zones to reduce the risk of Single Point of Failure.

Configuring ingresses

To create an ingress upon installation, simply set the following keys in your override-values.yaml file:

ingress:
  enabled: true
  hostname: stream.lab
  tls: true