K8s: add more secrets and connectivity info

content/operate/kubernetes/networking/_index.md

@@ -13,6 +13,12 @@ weight: 40
 
 Configure networking and external access for your Redis Enterprise deployment on Kubernetes. By default, Kubernetes doesn't allow external access to your Redis databases. Redis Enterprise for Kubernetes provides several methods to route external traffic to your clusters and databases.
 
+## Database connectivity
+
+Connect applications to your Redis Enterprise databases:
+
+- [Database connectivity]({{< relref "/operate/kubernetes/networking/database-connectivity" >}}) - Comprehensive guide to in-cluster and external database access, service discovery, and credentials management
+
 ## External routing methods
 
 Choose the appropriate method for your environment to enable external access:
@@ -29,16 +35,14 @@ For Active-Active databases, configure automatic ingress creation:
 
 ## External routing using Redis Enterprise for Kubernetes
 
-Every time a RedisEnterpriseDatabase (REDB), Redis Enterprise Active-Active database (REAADB), or Redis Enterprise cluster (REC) is created, the Redis Enterprise operator automatically creates a [service](https://kubernetes.io/docs/concepts/services-networking/service/) to allow requests to be routed to that resource.
-
-Redis Enterprise supports three [types of services](https://kubernetes.io/docs/concepts/services-networking/service/#publishing-services-service-types) for accessing databases: `ClusterIP`, `headless`, or `LoadBalancer`.
-
-By default, the operator creates a `ClusterIP` type service, which exposes a cluster-internal IP and that can only be accessed from within the K8s cluster. For requests to be routed from outside the K8s cluster, you need an [Ingress](https://kubernetes.io/docs/concepts/services-networking/ingress/) (or [route](https://docs.openshift.com/container-platform/4.12/networking/routes/route-configuration.html) if you are using OpenShift). See [kubernetes.io](https://kubernetes.io/docs/) for more details on [Ingress](https://kubernetes.io/docs/concepts/services-networking/ingress/) and [Ingress controllers](https://kubernetes.io/docs/concepts/services-networking/ingress-controllers/).
+The Redis Enterprise operator automatically creates Kubernetes services for database access. For external access from outside the cluster, you need to configure additional routing methods:
 
 - To use NGINX or HAProxy Ingress controllers, see [Ingress routing]({{< relref "/operate/kubernetes/networking/ingress" >}}).
 - To use OpenShift routes, see [OpenShift routes]({{< relref "/operate/kubernetes/networking/routes" >}}).
 - To use Istio as an Ingress controller, see [Istio Ingress routing]({{< relref "/operate/kubernetes/networking/istio-ingress" >}})
 
+For comprehensive information about service types, in-cluster access, and connectivity patterns, see [Database connectivity]({{< relref "/operate/kubernetes/networking/database-connectivity" >}}).
+
 ## `ingressOrRouteSpec` for Active-Active databases
 
 Versions 6.4.2 or later of Redis Enterprise for Kubernetes include a feature for ingress configuration. The `ingressOrRouteSpec` field is available in the RedisEnterpriseCluster spec to automatically create an Ingress (or route) for the API service and databases (REAADB) on that REC. See [REC external routing]({{< relref "/operate/kubernetes/networking/ingressorroutespec" >}}) for more details.

content/operate/kubernetes/networking/database-connectivity.md

@@ -0,0 +1,294 @@
+---
+Title: Database connectivity
+alwaysopen: false
+categories:
+- docs
+- operate
+- kubernetes
+description: Connect applications to Redis Enterprise databases in Kubernetes clusters with in-cluster and external access patterns.
+linkTitle: Database connectivity
+weight: 1
+---
+
+Connecting applications to Redis Enterprise databases in Kubernetes involves understanding service discovery, credentials management, and access patterns. This guide covers the essential connectivity aspects unique to Kubernetes deployments.
+
+## Service types and access patterns
+
+When you create a RedisEnterpriseDatabase (REDB), the Redis Enterprise operator automatically creates Kubernetes services to route traffic to your database. Understanding these service types is crucial for proper connectivity.
+
+### Default service creation
+
+By default, the operator creates two services for each database:
+
+- ClusterIP service - Provides a stable cluster-internal IP address
+- Headless service - Enables direct pod-to-pod communication and service discovery
+
+Both services are created in the same namespace as your database and follow predictable naming conventions.
+
+### Service types
+
+Redis Enterprise supports three service types for database access:
+
+| Service Type | Access Scope | Use Case |
+|--------------|--------------|----------|
+| `ClusterIP` | Cluster-internal only | Applications running within the same Kubernetes cluster |
+| `headless` | Cluster-internal only | Direct pod access, service discovery, StatefulSet scenarios |
+| `LoadBalancer` | External access | Applications outside the Kubernetes cluster |
+
+To configure the service type, use the `databaseServiceType` field in your REC's `servicesRiggerSpec`.
+
+## In-cluster database access
+
+For applications running within your Kubernetes cluster, use the automatically created services to connect to your databases.
+
+### Retrieve connection information
+
+Database connection details are stored in a Kubernetes secret maintained by the database controller. This secret contains:
+
+- Database port (`port`)
+- Service names (`service_names`) 
+- Database password (`password`)
+
+1. Get the secret name from your database resource:
+
+   ```sh
+   kubectl get redb <database-name> -o jsonpath="{.spec.databaseSecretName}"
+   ```
+
+   The secret name typically follows the pattern `redb-<database-name>`.
+
+2. Retrieve the database port:
+
+   ```sh
+   kubectl get secret redb-<database-name> -o jsonpath="{.data.port}" | base64 --decode
+   ```
+
+3. Get available service names:
+
+   ```sh
+   kubectl get secret redb-<database-name> -o jsonpath="{.data.service_names}" | base64 --decode
+   ```
+
+4. Retrieve the database password:
+
+   ```sh
+   kubectl get secret redb-<database-name> -o jsonpath="{.data.password}" | base64 --decode
+   ```
+
+### Service naming and DNS resolution
+
+Services follow standard Kubernetes DNS naming conventions:
+
+- Service FQDN: `<service-name>.<namespace>.svc.cluster.local`
+- Short name: `<service-name>` (within the same namespace)
+
+For a database named `mydb` in namespace `production`, the service names would be:
+- ClusterIP service: `mydb.production.svc.cluster.local`
+- Headless service: `mydb-headless.production.svc.cluster.local`
+
+### Connect from within the cluster
+
+Use any service name from the `service_names` list to connect:
+
+```sh
+redis-cli -h <service-name> -p <port>
+```
+
+Then authenticate with the retrieved password:
+
+```sh
+auth <password>
+```
+
+## External database access
+
+To access databases from outside the Kubernetes cluster, you need to configure external routing. Currently supported methods for external access are ingress controllers or OpenShift routes.
+
+### Ingress controllers
+
+Redis Enterprise for Kubernetes only supports the following ingress controllers for external database access:
+
+- NGINX Ingress - Supports SSL passthrough for Redis connections
+- HAProxy Ingress - Built-in SSL passthrough support  
+- Istio Gateway - Service mesh integration with advanced traffic management
+
+See [Ingress routing]({{< relref "/operate/kubernetes/networking/ingress" >}}) for detailed configuration steps.
+
+### OpenShift routes
+
+OpenShift users can leverage routes for external access:
+
+```yaml
+apiVersion: route.openshift.io/v1
+kind: Route
+metadata:
+  name: redis-route
+spec:
+  to:
+    kind: Service
+    name: <database-service-name>
+  port:
+    targetPort: redis
+  tls:
+    termination: passthrough
+```
+
+See [OpenShift routes]({{< relref "/operate/kubernetes/networking/routes" >}}) for complete setup instructions.
+
+## Service ports and configuration
+
+### Default port behavior
+
+- Redis Enterprise databases use dynamic port allocation
+- Port numbers are assigned automatically during database creation
+- The actual port is stored in the database secret
+
+### Custom port configuration
+
+You can specify custom ports using the `databasePort` field in your REDB specification:
+
+```yaml
+apiVersion: app.redislabs.com/v1alpha1
+kind: RedisEnterpriseDatabase
+metadata:
+  name: mydb
+spec:
+  memorySize: 256MB
+  databasePort: 6379
+```
+
+Custom ports replace the default service port and are reflected in the database secret.
+
+## Credentials and secrets management
+
+### Database secrets structure
+
+Each database has an associated Kubernetes secret containing connection details:
+
+```yaml
+apiVersion: v1
+kind: Secret
+metadata:
+  name: redb-<database-name>
+type: Opaque
+data:
+  port: <base64-encoded-port>
+  service_names: <base64-encoded-service-list>
+  password: <base64-encoded-password>
+```
+
+### Using secrets in applications
+
+Reference database secrets in your application deployments:
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: my-app
+spec:
+  template:
+    spec:
+      containers:
+      - name: app
+        image: my-app:latest
+        env:
+        - name: REDIS_HOST
+          value: "<service-name>"
+        - name: REDIS_PORT
+          valueFrom:
+            secretKeyRef:
+              name: redb-<database-name>
+              key: port
+        - name: REDIS_PASSWORD
+          valueFrom:
+            secretKeyRef:
+              name: redb-<database-name>
+              key: password
+```
+
+### Default user configuration
+
+By default, databases create a default user with full access. You can disable this behavior:
+
+```yaml
+apiVersion: app.redislabs.com/v1alpha1
+kind: RedisEnterpriseDatabase
+metadata:
+  name: mydb
+spec:
+  memorySize: 256MB
+  defaultUser: false
+```
+
+When `defaultUser` is disabled, the database secret is not created, and you must configure custom authentication.
+
+## Connection examples
+
+### Python application
+
+```python
+import redis
+import base64
+import os
+
+# Read from Kubernetes secret (mounted as environment variables)
+host = os.getenv('REDIS_HOST')
+port = int(os.getenv('REDIS_PORT'))
+password = os.getenv('REDIS_PASSWORD')
+
+# Create Redis connection
+r = redis.Redis(host=host, port=port, password=password, decode_responses=True)
+
+# Test connection
+r.ping()
+```
+
+### Node.js application
+
+```javascript
+const redis = require('redis');
+
+const client = redis.createClient({
+  host: process.env.REDIS_HOST,
+  port: process.env.REDIS_PORT,
+  password: process.env.REDIS_PASSWORD
+});
+
+client.on('connect', () => {
+  console.log('Connected to Redis');
+});
+```
+
+## Troubleshooting connectivity
+
+### Common issues
+
+1. Connection refused - Verify service names and ports from the database secret
+2. Authentication failed - Check password encoding and special characters
+3. DNS resolution - Ensure applications use correct service FQDNs
+4. Network policies - Verify Kubernetes network policies allow traffic
+
+### Debugging steps
+
+1. Verify service creation:
+   ```sh
+   kubectl get services -l app=redis-enterprise
+   ```
+
+2. Check service endpoints:
+   ```sh
+   kubectl get endpoints <service-name>
+   ```
+
+3. Test connectivity from within cluster:
+   ```sh
+   kubectl run redis-test --image=redis:latest -it --rm -- redis-cli -h <service-name> -p <port>
+   ```
+
+## Related topics
+
+- [Ingress routing]({{< relref "/operate/kubernetes/networking/ingress" >}}) - Configure external access with ingress controllers
+- [OpenShift routes]({{< relref "/operate/kubernetes/networking/routes" >}}) - External access using OpenShift routes  
+- [Database controller]({{< relref "/operate/kubernetes/re-databases/db-controller" >}}) - Database lifecycle management
+- [Security]({{< relref "/operate/kubernetes/security" >}}) - TLS configuration and access control

content/operate/kubernetes/re-databases/_index.md

@@ -37,6 +37,7 @@ Explore advanced database features and configurations:
 
 Connect applications to your Redis Enterprise databases:
 
+- [Database connectivity]({{< relref "/operate/kubernetes/networking/database-connectivity" >}}) - Comprehensive guide to in-cluster and external database access, service discovery, and credentials management
 - [Networking]({{< relref "/operate/kubernetes/networking" >}}) - Configure ingress, routes, and service exposure for database access
 - [Security]({{< relref "/operate/kubernetes/security" >}}) - Set up TLS, authentication, and access control for secure database connections