more changes related to ENC implementation

howto/puppet.md

@@ -1120,12 +1120,18 @@ All paths below are relative to the root of that git repository.
 - `modules` includes roles, profiles, and classes that make the bulk
   of our configuration.
 
-- each node is assigned a "role" through Hiera, in
-  `hiera/nodes/$FQDN.yaml`
+- each node is assigned a "role" through the ENC, in
+  `hiera-enc/nodes/$FQDN.yaml`
 
-  To be more accurate, Hiera assigns a Puppet class to each node,
-  although each node should have only one special purpose class, a
-  "role", see [issue 40030][] for progress on that transition.
+  To be more accurate, the ENC assigns top-scope `$role` variable to
+  each node, which is in turn used to include a `role::$rolename`
+  class on each node. This occurs in the default node definition in
+  `manifests/site.pp`.
+
+  Some nodes include a list of classes, inherited from the previous
+  Hiera-based setup, but we're in the process of transitioning all
+  nodes to single role classes, see [issue 40030][] for progress on
+  this work.
 
 [issue 40030]: https://gitlab.torproject.org/tpo/tpa/team/-/issues/40030
 
@@ -1146,8 +1152,9 @@ All paths below are relative to the root of that git repository.
   - `ferm`'s `def.conf` template (`modules/ferm/templates/defs.conf.erb`)
 
 - The root of definitions and execution is in Puppet is found in
-  the `manifests/site.pp` file, but this file is now mostly empty, in
-  favor of Hiera.
+  the `manifests/site.pp` file. Its purpose is to include a role class
+  for the node as well as a number of other classes which are common
+  for all nodes.
 
 Note that the above is the current state of the file hierarchy. As
 part Hiera transition ([issue 30020][]), a lot of the above