k8s-namespace-sync

K8s Namespace Sync

K8s Namespace Sync is a Kubernetes controller that automatically synchronizes Secrets and ConfigMaps across multiple namespaces within a Kubernetes cluster.

Features

• Automatic synchronization of Secrets and ConfigMaps across namespaces
• Automatic detection and synchronization of changes in source namespace
• Automatic exclusion of system namespaces (kube-system, kube-public, etc.)
• Support for manually excluding specific namespaces
• Prometheus metrics support
• Synchronization status monitoring

Installation

kubectl apply -f https://raw.githubusercontent.com/somaz94/k8s-namespace-sync/main/release/install.yaml

Usage

1. Create a Secret or ConfigMap in the source namespace:

apiVersion: v1
kind: Secret
metadata:
  name: test-secret
  namespace: default
type: Opaque
stringData:
  username: admin
  password: secret123
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: test-configmap
  namespace: default
data:
  key1: value1
  key2: value2

1. Create a NamespaceSync CR:

Basic synchronization:

apiVersion: sync.nsync.dev/v1
kind: NamespaceSync
metadata:
  name: namespacesync-sample
spec:
  sourceNamespace: default
  configMapName: test-configmap
  secretName: test-secret

Basic apply the CR:

kubectl apply -f https://raw.githubusercontent.com/somaz94/k8s-namespace-sync/main/release/examples/sync_v1_namespacesync.yaml

With excluded namespaces:

apiVersion: sync.nsync.dev/v1
kind: NamespaceSync
metadata:
  name: namespacesync-sample-with-exclude
spec:
  sourceNamespace: default
  configMapName: test-configmap
  secretName: test-secret
  exclude:
    - test-ns2
    - test-ns3

Exclude apply the CR:

kubectl apply -f https://raw.githubusercontent.com/somaz94/k8s-namespace-sync/main/release/examples/sync_v1_namespacesync_with_exclude.yaml

Verification

1. Check synchronization status:

kubectl get namespacesync namespacesync-sample -o yaml

1. Verify resources in other namespaces:

kubectl get secret test-secret -n target-namespace
kubectl get configmap test-configmap -n target-namespace

Excluded Namespaces

The following namespaces are automatically excluded from synchronization:

• kube-system
• kube-public
• kube-node-lease
• k8s-namespace-sync-system

Additionally, you can manually exclude specific namespaces using the exclude field in the NamespaceSync CR.

Metrics

The following Prometheus metrics are available:

• namespacesync_sync_success_total: Number of successful synchronizations
• namespacesync_sync_failure_total: Number of failed synchronizations

Cleanup

1. Delete the NamespaceSync CR:

kubectl delete namespacesync namespacesync-sample
kubectl delete namespacesync namespacesync-sample-with-exclude

1. Remove the controller:

kubectl delete -f https://raw.githubusercontent.com/somaz94/k8s-namespace-sync/main/release/install.yaml

Contributing

Issues and pull requests are welcome.

License

This project is licensed under the MIT License - see the LICENSE file for details.