Database Setup

The NeMo Helix uses a SQL-based database to store entities such as workspaces, jobs, and other records.

By default, the NeMo Helix Helm chart deploys an embedded PostgreSQL instance (a StatefulSet using the official Postgres image) with simplified authentication to enable quick installation. This should not be used for production use, and an external PostgreSQL instance is recommended.

Preserve embedded PostgreSQL claim-template labels on upgrade

Starting with chart v0.7.3, postgresql.persistence.claimTemplateLabels lets existing installations retain the labels on the embedded PostgreSQL StatefulSet’s data volume claim template. Kubernetes treats this template as immutable, so changing its labels during a Helm upgrade can cause the upgrade to fail.

Before upgrading an older installation, inspect the existing StatefulSet:

kubectl get statefulset <postgres-statefulset> --namespace <namespace> -o yaml

Copy the complete label map from the data entry under spec.volumeClaimTemplates[].metadata.labels into postgresql.persistence.claimTemplateLabels in your Helm values. Copy the claim-template labels, not the StatefulSet or Pod labels. Retain those exact values on every future upgrade, including any old chart or application version labels; do not replace them with the new release version. Supplied labels override the default app.kubernetes.io/component: postgres label.

The default {} keeps the existing chart behavior for fresh installations. This setting addresses claim-template labels only. Preserve your existing release name, resource names, storage configuration, and secrets encryption key and its Secret reference as well. External PostgreSQL installations are not affected by this embedded-storage setting.

External PostgreSQL Database

To use an external PostgreSQL database in the Helm chart:

1. Set postgresql.enabled: false and configure externalDatabase.
2. Choose one of the following approaches to create a Kubernetes secret with your credentials:

Option 1: Use a full connection URI

Use a secret that holds the full database connection URI and reference it with uriSecret. This is the best option when you need to configure TLS/SSL or want a single secret for the connection string.

1. Create a secret containing the connection URI (optionally with SSL parameters):

kubectl create secret generic my-db-uri-secret --from-literal=uri='postgresql://nemo@db-host:5432/nemohelix'

For SSL, include sslmode in the URI:

kubectl create secret generic my-db-uri-secret --from-literal=uri='postgresql://nemo@db-host:5432/nemohelix?sslmode=require'

2. Configure the chart to use that secret:

postgresql:
  enabled: false
externalDatabase:
  uriSecret:
    name: my-db-uri-secret
    key: uri

When uriSecret is set, the platform uses the URI from the secret and ignores host, port, user, database, and existingSecret.

Option 2: Configure individual connection details

Use individual host, port, user, and database values and a secret that contains only the password. The platform builds the connection from these values.

1. Create a secret containing the password (the key must be password, or set existingSecretPasswordKey to the key name in your secret):

kubectl create secret generic my-db-password-secret --from-literal=password='my-password'

Or define the secret in YAML:

apiVersion: v1
kind: Secret
metadata:
  name: my-db-password-secret
type: Opaque
stringData:
  password: my-password

2. Configure the chart with connection details and the secret name:

postgresql:
  enabled: false
externalDatabase:
  host: db-host.example.com
  port: 5432
  user: nemo
  database: nemohelix
  existingSecret: my-db-password-secret
  existingSecretPasswordKey: "password" # key in the secret that holds the password