Merge pull request #47592 from lpettyjo/BZ2081804

BZ2081804:Update CSI architecture diagram

Author: lpettyjo

images/csi-arch-rev1.png

@@ -14,7 +14,7 @@ storage driver.
 The following diagram provides a high-level overview about the components
 running in pods in the {product-title} cluster.
 
-image::csi-arch.png["Architecture of CSI components"]
+image::csi-arch-rev1.png["Architecture of CSI components"]
 
 It is possible to run multiple CSI drivers for different storage back ends.
 Each driver needs its own external controllers deployment and daemon set

modules/persistent-storage-csi-architecture.adoc

@@ -6,8 +6,10 @@
 = External CSI controllers
 
 External CSI Controllers is a deployment that deploys one or more pods
-with three containers:
+with five containers:
 
+* The snapshotter container watches `VolumeSnapshot` and `VolumeSnapshotContent` objects and is responsible for the creation and deletion of `VolumeSnapshotContent` object.
+* The resizer container is a sidecar container that watches for `PersistentVolumeClaim` updates and triggers `ControllerExpandVolume` operations against a CSI endpoint if you request more storage on `PersistentVolumeClaim` object.
 * An external CSI attacher container translates `attach` and `detach`
 calls from {product-title} to respective `ControllerPublish` and
 `ControllerUnpublish` calls to the CSI driver.