Documentation for Custom Volumes/Volume Mounts

Author: Bobbins228

Diff for: docs/cluster-configuration.md

@@ -22,9 +22,60 @@ cluster = Cluster(ClusterConfiguration(
     image="quay.io/project-codeflare/ray:latest-py39-cu118", # Mandatory Field
     machine_types=["m5.xlarge", "g4dn.xlarge"],
     labels={"exampleLabel": "example", "secondLabel": "example"},
+    volumes=[], # See Custom Volumes/Volume Mounts
+    volume_mounts=[], # See Custom Volumes/Volume Mounts
 ))
 ```
 
 The `labels={"exampleLabel": "example"}` parameter can be used to apply additional labels to the RayCluster resource.
 
 After creating their`cluster`, a user can call `cluster.up()` and `cluster.down()` to respectively create or remove the Ray Cluster.
+
+## Custom Volumes/Volume Mounts
+To add custom Volumes and Volume Mounts to your Ray Cluster you need to create two lists `volumes` and `volume_mounts`.
+The lists consist of `V1Volume` and `V1VolumeMount` objects respectively.<br>
+Populating these parameters will create Volumes and Volume Mounts for the head and each worker pod.
+
+Below is an example of how a user would create these lists using the Python Kubernetes Library.
+
+```python
+from kubernetes.client import V1Volume, V1VolumeMount, V1EmptyDirVolumeSource, V1ConfigMapVolumeSource, V1KeyToPath, V1SecretVolumeSource
+# In this example we are using the Config Map, EmptyDir and Secret Volume types
+volume_mounts_list = [
+    V1VolumeMount(
+        mount_path="/home/ray/test1",
+        name = "test"
+    ),
+    V1VolumeMount(
+        mount_path = "/home/ray/test2",
+        name = "test2",
+    ),
+    V1VolumeMount(
+        mount_path = "/home/ray/test3",
+        name = "test3",
+    )
+]
+
+volumes_list = [
+    V1Volume(
+        name="test",
+        empty_dir=V1EmptyDirVolumeSource(size_limit="2Gi"),
+    ),
+    V1Volume(
+        name="test2",
+        config_map=V1ConfigMapVolumeSource(
+            name="test-config-map",
+            items=[V1KeyToPath(key="test", path="data.txt")]
+        )
+    ),
+    V1Volume(
+        name="test3",
+        secret=V1SecretVolumeSource(
+            secret_name="test-secret"
+        )
+    )
+]
+```
+
+For more information on creating Volumes and Volume Mounts with Python check out the Python Kubernetes docs ([Volumes](https://github.com/kubernetes-client/python/blob/master/kubernetes/docs/V1Volume.md), [Volume Mounts](https://github.com/kubernetes-client/python/blob/master/kubernetes/docs/V1VolumeMount.md)).
+You can also find further information on Volumes and Volume Mounts by visiting the Kubernetes [documentation](https://kubernetes.io/docs/concepts/storage/volumes/).