[k8s][docs] Add containers example to pod_config example

docs/source/reference/config.rst

@@ -180,17 +180,28 @@ Available fields and semantics:
     # in the Kubernetes API:
     # https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.26/#pod-v1-core
     #
-    # Example use cases: adding custom labels to SkyPilot pods, specifying
-    # imagePullSecrets for pulling images from private registries, overriding
-    # the default runtimeClassName etc.
+    # Some example use cases are shown below. All fields are optional.
     pod_config:
       metadata:
         labels:
-          my-label: my-value
+          my-label: my-value    # Custom labels to SkyPilot pods
       spec:
-        runtimeClassName: nvidia
+        runtimeClassName: nvidia    # Custom runtimeClassName for GPU pods. Required on K3s.
         imagePullSecrets:
-          - name: my-secret
+          - name: my-secret     # Pull images from a private registry using a secret
+        containers:
+          - env:                # Custom environment variables for the pod, e.g., for proxy
+            - name: HTTP_PROXY
+              value: http://proxy-host:3128
+            volumeMounts:       # Custom volume mounts for the pod
+              - mountPath: /foo
+                name: example-volume
+                readOnly: true
+        volumes:
+          - name: example-volume
+            hostPath:
+              path: /tmp
+              type: Directory
 
   # Advanced OCI configurations (optional).
   oci:

docs/source/reference/kubernetes/index.rst

@@ -177,6 +177,25 @@ FAQs
 
   For isolation, you can create separate Kubernetes namespaces and set them in the kubeconfig distributed to users. SkyPilot will use the namespace set in the kubeconfig for running all tasks.
 
+* **How can I specify custom configuration for the pods created by SkyPilot?**
+
+  You can override the pod configuration used by SkyPilot by setting the :code:`pod_config` key in :code:`~/.sky/config.yaml`.
+  The value of :code:`pod_config` should be a dictionary that follows the `Kubernetes Pod API <https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.22/#pod-v1-core>`_.
+
+  For example, to set custom environment variables in the pod, you can add the following to your :code:`~/.sky/config.yaml` file:
+
+  .. code-block:: yaml
+
+      kubernetes:
+        pod_config:
+          spec:
+            containers:
+              - env:
+                - name: MY_ENV_VAR
+                  value: MY_ENV_VALUE
+
+  For more details refer to :ref:`config-yaml`.
+
 Features and Roadmap
 --------------------