Merge pull request #465 from TomSweeneyRedHat/dev/tsweeney/registriesman

Update registries.conf man

docs/registries.conf.5.md

@@ -7,35 +7,44 @@ registries.conf - Syntax of System Registry Configuration File
 
 # DESCRIPTION
 The REGISTRIES configuration file is a system-wide configuration file for container image
-registries. The file format is TOML.
+registries. The file format is TOML.  The valid categories are: 'registries.search',
+'registries.insecure', and 'registries.block'.
 
 # FORMAT
-The TOML_format is used to build simple list format for registries under two
-categories: `search` and `insecure`. You can list multiple registries using
-as a comma separated list.
+The TOML_format is used to build a simple list format for registries under three
+categories: `registries.search`, `registries.insecure`, and `registries.block`.
+You can list multiple registries using a comma separated list.
 
 Search registries are used when the caller of a container runtime does not fully specify the
 container image that they want to execute.  These registries are prepended onto the front
- of the specified container image until the named image is found at a registry.
+of the specified container image until the named image is found at a registry.
 
 Insecure Registries.  By default container runtimes use TLS when retrieving images
 from a registry.  If the registry is not setup with TLS, then the container runtime
 will fail to pull images from the registry. If you add the registry to the list of
 insecure registries then the container runtime will attempt use standard web protocols to
 pull the image.  It also allows you to pull from a registry with self-signed certificates.
-Note insecure registries can be used for any registry, not just the
-registries listed under search.
+Note insecure registries can be used for any registry, not just the registries listed
+under search.
 
-The following example configuration defines two searchable registries and one
-insecure registry.
+Block Registries.  The registries in this category are are not pulled from when
+retrieving images.
+
+# EXAMPLE
+The following example configuration defines two searchable registries, one
+insecure registry, and two blocked registries.
 
 ```
 [registries.search]
-registries = ["registry1.com", "registry2.com"]
+registries = ['registry1.com', 'registry2.com']
 
 [registries.insecure]
-registries = ["registry3.com"]
+registries = ['registry3.com']
+
+[registries.block]
+registries = ['registry.untrusted.com', 'registry.unsafe.com']
 ```
 
 # HISTORY
 Aug 2017, Originally compiled by Brent Baude <bbaude@redhat.com>
+Jun 2018, Updated by Tom Sweeney <tsweeney@redhat.com>