diff --git a/api-ref/source/servers-actions.inc b/api-ref/source/servers-actions.inc
index 1d6f27a0b3a4..f95d88ca79d4 100644
--- a/api-ref/source/servers-actions.inc
+++ b/api-ref/source/servers-actions.inc
@@ -283,9 +283,28 @@ image in the image back end that OpenStack Image service manages.
 The server must exist.
 
 You can only create a new image from the server when its status is ``ACTIVE``,
-``SHUTOFF``, ``PAUSED``, or ``SUSPENDED``.
+``SHUTOFF``, ``SUSPENDED`` or ``PAUSED``
+(``PAUSED`` is only supported for image-backed servers).
 
-The connection to the Image service is valid.
+The project must have sufficient volume snapshot quota in the block storage
+service when the server has attached volumes.
+If the project does not have sufficient volume snapshot quota,
+the API returns a 403 error.
+
+**Asynchronous Postconditions**
+
+A snapshot image will be created in the Image service.
+
+In the image-backed server case, volume snapshots of attached volumes will not
+be created.
+In the volume-backed server case,
+volume snapshots will be created for all volumes attached to the server and
+then those will be represented with a ``block_device_mapping`` image property
+in the resulting snapshot image in the Image service.
+If that snapshot image is used later to create a new server,
+it will result in a volume-backed server where the root volume is created
+from the snapshot of the original root volume. The volumes created from
+the snapshots of the original other volumes will be attached to the server.
 
 **Troubleshooting**