OpenMetadata helm chart depends on Airflow and Airflow expects a persistent disk that support ReadWriteMany (the volume can be mounted as read-write by many nodes).
This guide assumes you have NFS Server already setup with Hostname or IP Address which is reachable from your on premises Kubernetes cluster and you have configured a path to be used for OpenMetadata Airflow Helm Dependency.
{% /note %}
### Dynamic Provisioning using StorageClass
To provision PersistentVolume dynamically using the StorageClass, you need to install the NFS provisioner.
It is recommended to use [nfs-subdir-external-provisioner](https://github.com/kubernetes-sigs/nfs-subdir-external-provisioner) helm charts for this case.
This will create a new StorageClass with `nfs-subdir-external-provisioner`. You can view the same using the kubectl command `kubectl get storageclass -n nfs-provisioner`.
## Provision NFS backed PVC for Airflow DAGs and Airflow Logs
### Code Samples for PVC for Airflow DAGs
```yaml
# dags_pvc.yml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
namespace: default
name: openmetadata-dependencies-dags
labels:
storage.k8s.io/name: nfs
app: airflow
spec:
accessModes:
- ReadWriteMany
storageClassName: nfs-client
resources:
requests:
storage: 1Gi
```
Create Persistent Volumes and Persistent Volume claims with the below command.
```commandline
kubectl create -f dags_pvc.yml
```
### Code Samples for PVC for Airflow Logs
```yaml
# logs_pvc.yml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
namespace: default
name: openmetadata-dependencies-logs
labels:
storage.k8s.io/name: nfs
app: airflow
spec:
accessModes:
- ReadWriteMany
storageClassName: nfs-client
resources:
requests:
storage: 10Gi
```
Create Persistent Volumes and Persistent Volume claims with the below command.
```commandline
kubectl create -f logs_pvc.yml
```
## Change owner and permission manually on disks
Since airflow pods run as non root users, they would not have write access on the nfs server volumes. In order to fix the permission here, spin up a pod with persistent volumes attached and run it once.
```yaml
# permissions_pod.yml
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: null
labels:
run: my-permission-pod
name: my-permission-pod
spec:
containers:
- image: busybox
name: my-permission-pod
volumeMounts:
- name: airflow-dags
mountPath: /airflow-dags
- name: airflow-logs
mountPath: /airflow-logs
command:
- "chown -R 50000 /airflow-dags /airflow-logs"
# if needed
- "chmod -R a+rwx /airflow-dags"
volumes:
- name: airflow-logs
persistentVolumeClaim:
claimName: openmetadata-dependencies-logs
- name: airflow-dags
persistentVolumeClaim:
claimName: openmetadata-dependencies-dags
dnsPolicy: ClusterFirst
restartPolicy: Always
```
{% note %}
Airflow runs the pods with linux user name as airflow and linux user id as 50000.
{% /note %}
Run the below command to create the pod and fix the permissions
```commandline
kubectl create -f permissions_pod.yml
```
## Create OpenMetadata dependencies Values
Override openmetadata dependencies airflow helm values to bind the nfs persistent volumes for DAGs and logs.
