Merge "Fix docs to require docker config on all nodes"

1 files changed, 22 insertions, 7 deletions

diff --git a/doc/multinode.rst b/doc/multinode.rst
index da624066b..24938edaf 100644
--- a/doc/multinode.rst
+++ b/doc/multinode.rst
@@ -6,20 +6,35 @@ Multinode Deployment of Kolla
 
 .. _deploy_a_registry:
 
-Deploy a registry (required for multinode)
-==========================================
+Deploy a registry
+=================
 
 A Docker registry is a locally hosted registry that replaces the need to pull
-from the Docker Hub to get images. A local registry is required for a multinode
-Kolla deployment.
+from the Docker Hub to get images. Kolla can function with or without a local
+registry, however for a multinode deployment some type of registry is mandatory.
+Only one registry must be deployed, although HA features exist for registry
+services.
+
+The Docker registry prior to version 2.3 has extremely bad performance because
+all container data is pushed for every image rather than taking advantage of
+Docker layering to optimize push operations. For more information reference
+`pokey registry <https://github.com/docker/docker/issues/14018>`__.
 
 The Kolla community recommends using registry 2.3 or later. To deploy registry
-with version greater than 2.3, do the following:
+with version 2.3 or later, do the following:
 
 ::
 
     tools/start-registry
 
+.. _configure_docker_all_nodes:
+
+Configure Docker on all nodes
+=============================
+
+.. note:: As the subtitle for this section implies, these steps should be
+          applied to all nodes, not just the deployment node.
+
 After starting the registry, it is necessary to instruct Docker that it will
 be communicating with an insecure registry. To enable insecure registry
 communication on CentOS, modify the ``/etc/sysconfig/docker`` file to contain
@@ -88,8 +103,8 @@ Edit the Inventory File
 
 The ansible inventory file contains all the information needed to determine
 what services will land on which hosts. Edit the inventory file in the kolla
-directory ``ansible/inventory/multinode`` or if kolla was installed with pip,
-it can be found in ``/usr/share/kolla``.
+directory ``ansible/inventory/multinode``. If kolla was installed with pip,
+the inventory file can be found in ``/usr/share/kolla``.
 
 Add the ip addresses or hostnames to a group and the services associated with
 that group will land on that host: