> ## Documentation Index > Fetch the complete documentation index at: https://docs.open-metadata.org/llms.txt > Use this file to discover all available pages before exploring further. # On-Prem Airflow Storage Setup | OpenMetadata Kubernetes Guide > Provision NFS-backed persistent volumes for Airflow DAGs and logs on on-premises Kubernetes and deploy OpenMetadata. # On-Prem Airflow Storage Setup This guide walks through provisioning NFS-backed PVCs for Airflow DAGs and logs on an on-premises Kubernetes cluster, then deploying OpenMetadata. For prerequisites and StorageClass setup, see the [On-Prem Kubernetes Deployment](/v1.12.x/deployment/kubernetes/on-prem) page. ## Provision NFS backed PVC for Airflow DAGs and Airflow Logs ### Code Samples for PVC for Airflow DAGs ```yaml theme={null} # 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 theme={null} kubectl create -f dags_pvc.yml ``` ### Code Samples for PVC for Airflow Logs ```yaml theme={null} # 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 theme={null} 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 theme={null} # 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 ``` Airflow runs the pods with linux username as airflow and linux user id as 50000. Run the below command to create the pod and fix the permissions ```commandline theme={null} 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. ```yaml theme={null} # values-dependencies.yml airflow: airflow: extraVolumeMounts: - mountPath: /airflow-logs name: nfs-airflow-logs - mountPath: /airflow-dags/dags name: nfs-airflow-dags extraVolumes: - name: nfs-airflow-logs persistentVolumeClaim: claimName: openmetadata-dependencies-logs - name: nfs-airflow-dags persistentVolumeClaim: claimName: openmetadata-dependencies-dags config: AIRFLOW__OPENMETADATA_AIRFLOW_APIS__DAG_GENERATED_CONFIGS: "/airflow-dags/dags" dags: path: /airflow-dags/dags persistence: enabled: false logs: path: /airflow-logs persistence: enabled: false ``` For more information on airflow helm chart values, please refer to [airflow-helm](https://artifacthub.io/packages/helm/airflow-helm/airflow/8.8.0). When deploying openmetadata dependencies helm chart, use the below command - ```commandline theme={null} helm install openmetadata-dependencies open-metadata/openmetadata-dependencies --values values-dependencies.yaml ``` The above command uses configurations defined [here](https://raw.githubusercontent.com/open-metadata/openmetadata-helm-charts/main/charts/deps/values.yaml). You can modify any configuration and deploy by passing your own `values.yaml` ```commandline theme={null} helm install openmetadata-dependencies open-metadata/openmetadata-dependencies --values ``` Once the openmetadata dependencies helm chart deployed, you can then run the below command to install the openmetadata helm chart - ```commandline theme={null} helm install openmetadata open-metadata/openmetadata ``` Again, this uses the values defined [here](https://github.com/open-metadata/openmetadata-helm-charts/blob/main/charts/openmetadata/values.yaml). Use the `--values` flag to point to your own YAML configuration if needed. ## Troubleshooting Starting with **OpenMetadata v1.12.4**, the dependency Helm chart no longer supports passing database passwords using individual Kubernetes secret keys (for example, `passwordSecret` and `passwordSecretKey`). Instead, database credentials must be provided via a **single Kubernetes Secret** referenced using `metadataSecretName`. This secret must contain the **full database connection string**, including the password. ```yaml theme={null} data: metadataSecretName: your-connection-string-secret ``` This change applies **only to the dependency `values.yml` configuration** and aligns with the database configuration approach used by the **Airflow Helm chart**. ## FAQs ## Java Memory Heap Issue If your openmetadata pods are not in ready state at any point in time and the openmetadata pod logs speaks about the below issue - ``` Exception: java.lang.OutOfMemoryError thrown from the UncaughtExceptionHandler in thread "AsyncAppender-Worker-async-file-appender" Exception in thread "pool-5-thread-1" java.lang.OutOfMemoryError: Java heap space Exception in thread "AsyncAppender-Worker-async-file-appender" java.lang.OutOfMemoryError: Java heap space Exception in thread "dw-46" java.lang.OutOfMemoryError: Java heap space Exception in thread "AsyncAppender-Worker-async-console-appender" java.lang.OutOfMemoryError: Java heap space ``` This is due to the default JVM Heap Space configuration (1 GiB) being not enough for your workloads. In order to resolve this issue, head over to your custom openmetadata helm values and append the below environment variable ```yaml theme={null} extraEnvs: - name: OPENMETADATA_HEAP_OPTS value: "-Xmx2G -Xms2G" ``` The flag `Xmx` specifies the maximum memory allocation pool for a Java virtual machine (JVM), while `Xms` specifies the initial memory allocation pool. Upgrade the helm charts with the above changes using the following command `helm upgrade --install openmetadata open-metadata/openmetadata --values --namespace `. Update this command your `values.yml` filename and `namespaceName` where you have deployed OpenMetadata in Kubernetes. ## PostgreSQL Issue permission denied to create extension "pgcrypto" If you are facing the below issue with PostgreSQL as Database Backend for OpenMetadata Application, ``` Message: ERROR: permission denied to create extension "pgcrypto" Hint: Must be superuser to create this extension. ``` It seems the Database User does not have sufficient privileges. In order to resolve the above issue, grant usage permissions to the PSQL User. ```sql theme={null} GRANT USAGE ON SCHEMA schema_name TO ; GRANT CREATE ON EXTENSION pgcrypto TO ; ``` In the above command, replace `` with the sql user used by OpenMetadata Application to connect to PostgreSQL Database. ## How to extend and use custom docker images with OpenMetadata Helm Charts ? ## Extending OpenMetadata Server Docker Image ### 1. Create a `Dockerfile` based on `docker.open-metadata.org/openmetadata/server` OpenMetadata helm charts uses official published docker images from [DockerHub](https://hub.docker.com/u/openmetadata). A typical scenario will be to install organization certificates for connecting with inhouse systems. For Example - ``` FROM docker.open-metadata.org/openmetadata/server:x.y.z WORKDIR /home/ COPY . RUN update-ca-certificates ``` where `docker.open-metadata.org/openmetadata/server:x.y.z` needs to point to the same version of the OpenMetadata server, for example `docker.open-metadata.org/openmetadata/server:1.3.1`. This image needs to be built and published to the container registry of your choice. ### 2. Update your openmetadata helm values yaml The OpenMetadata Application gets installed as part of `openmetadata` helm chart. In this step, update the custom helm values using YAML file to point the image created in the previous step. For example, create a helm values file named `values.yaml` with the following contents - ```yaml theme={null} ... image: repository: # Overrides the image tag whose default is the chart appVersion. tag: ... ``` ### 3. Install / Upgrade your helm release Upgrade/Install your openmetadata helm charts with the below single command: ```bash theme={null} helm upgrade --install openmetadata open-metadata/openmetadata--values values.yaml ``` ## Extending OpenMetadata Ingestion Docker Image One possible use case where you would need to use a custom image for the ingestion is because you have developed your own custom connectors. You can find a complete working example of this [here](https://github.com/open-metadata/openmetadata-demo/tree/main/custom-connector). After you have your code ready, the steps would be the following: ### 1. Create a `Dockerfile` based on `docker.open-metadata.org/openmetadata/ingestion`: For example - ``` FROM docker.open-metadata.org/openmetadata/ingestion:x.y.z USER airflow # Let's use the home directory of airflow user WORKDIR /home/airflow # Install our custom connector COPY COPY setup.py . RUN pip install --no-deps . ``` where `docker.open-metadata.org/openmetadata/ingestion:x.y.z` needs to point to the same version of the OpenMetadata server, for example `docker.open-metadata.org/openmetadata/ingestion:1.3.1`. This image needs to be built and published to the container registry of your choice. ### 2. Update the airflow in openmetadata dependencies values YAML The ingestion containers (which is the one shipping Airflow) gets installed in the `openmetadata-dependencies` helm chart. In this step, we use our own custom values YAML file to point to the image we just created on the previous step. You can create a file named `values.deps.yaml` with the following contents: ```yaml theme={null} airflow: airflow: image: repository: # by default, openmetadata/ingestion tag: # by default, the version you are deploying, e.g., 1.1.0 pullPolicy: "IfNotPresent" ``` ### 3. Install / Upgrade helm release Upgrade/Install your openmetadata-dependencies helm charts with the below single command: ```bash theme={null} helm upgrade --install openmetadata-dependencies open-metadata/openmetadata-dependencies --values values.deps.yaml ``` ## How to disable MySQL and ElasticSearch from OpenMetadata Dependencies Helm Charts ? If you are using MySQL and ElasticSearch externally, you would want to disable the local installation of mysql and elasticsearch while installing OpenMetadata Dependencies Helm Chart. You can disable the MySQL and ElasticSearch Helm Dependencies by setting `enabled: false` value for each dependency. Below is the command to set helm values from Helm CLI - ```commandline theme={null} helm upgrade --install openmetadata-dependencies open-metadata/openmetadata-dependencies --set mysql.enabled=false --set elasticsearch.enabled=false ``` Alternatively, you can create a custom YAML file named `values.deps.yaml` to disable installation of MySQL and Elasticsearch . ```yaml theme={null} mysql: enabled: false ... elasticsearch: enabled: false ... ... ``` ## How to configure external database like PostgreSQL with OpenMetadata Helm Charts ? OpenMetadata Supports PostgreSQL as one of the Database Dependencies. OpenMetadata Helm Charts by default does not include PostgreSQL as Database Dependencies. In order to configure Helm Charts with External Database like PostgreSQL, follow the below guide to make the helm values change and upgrade / install OpenMetadata helm charts with the same. ## Upgrade Airflow Helm Dependencies Helm Charts to connect to External Database like PostgreSQL We ship [airflow-helm](https://github.com/airflow-helm/charts/tree/main/charts/airflow) as one of OpenMetadata Dependencies with default values to connect to MySQL Database as part of `externalDatabase` configurations. You can find more information on setting the `externalDatabase` as part of helm values [here](https://github.com/airflow-helm/charts/blob/main/charts/airflow/docs/faq/database/external-database.md). With OpenMetadata Dependencies Helm Charts, your helm values would look something like below - ```yaml theme={null} ... airflow: externalDatabase: type: postgresql host: port: 5432 database: user: passwordSecret: airflow-postgresql-secrets passwordSecretKey: airflow-postgresql-password ... ``` For the above code, it is assumed you are creating a kubernetes secret for storing Airflow Database login Credentials. A sample command to create the secret will be `kubectl create secret generic airflow-postgresql-secrets --from-literal=airflow-postgresql-password=`. ## Upgrade OpenMetadata Helm Charts to connect to External Database like PostgreSQL Update the `openmetadata.config.database.*` helm values for OpenMetadata Application to connect to External Database like PostgreSQL. With OpenMetadata Helm Charts, your helm values would look something like below - ```yaml theme={null} openmetadata: config: ... database: host: port: 5432 driverClass: org.postgresql.Driver dbScheme: postgresql dbUseSSL: true databaseName: auth: username: password: secretRef: openmetadata-postgresql-secrets secretKey: openmetadata-postgresql-password ``` For the above code, it is assumed you are creating a kubernetes secret for storing OpenMetadata Database login Credentials. A sample command to create the secret will be `kubectl create secret generic openmetadata-postgresql-secrets --from-literal=openmetadata-postgresql-password=`. Once you make the above changes to your helm values, run the below command to install/upgrade helm charts - ```commandline theme={null} helm upgrade --install openmetadata-dependencies open-metadata/openmetadata-dependencies --values <> --namespace helm upgrade --install openmetadata open-metadata/openmetadata --values <> --namespace ``` ## How to customize OpenMetadata Dependencies Helm Chart with custom helm values Our OpenMetadata Dependencies Helm Charts are internally depends on three sub-charts - * [Bitnami MySQL](https://artifacthub.io/packages/helm/bitnami/mysql/9.7.2) (helm chart version 9.7.2) * [OpenSearch](https://artifacthub.io/packages/helm/opensearch-project-helm-charts/opensearch/2.12.2) (helm chart version 2.12.2) * [Airflow](https://artifacthub.io/packages/helm/airflow-helm/airflow/8.8.0) (helm chart version 8.8.0) If you are looking to customize the deployments of any of the above dependencies, please refer to the above links for customizations of helm values for further references. By default, OpenMetadata Dependencies helm chart provides initial generic customization of these helm values in order to get you started quickly. You can refer to the openmetadata-dependencies helm charts default values [here](https://github.com/open-metadata/openmetadata-helm-charts/blob/main/charts/deps/values.yaml).