doc: add extended admin-group user documentation

Add the extended admin-group user documentation using affinity-maps.

Signed-off-by: Louis Scalbert <louis.scalbert@6wind.com>

3 files changed, 63 insertions, 2 deletions

diff --git a/doc/user/affinitymap.rst b/doc/user/affinitymap.rst
new file mode 100644
index 0000000000..b7dcb146c7
--- /dev/null
+++ b/doc/user/affinitymap.rst
@@ -0,0 +1,32 @@
+.. _affinity-map:
+
+*************
+Affinity Maps
+*************
+
+Affinity maps provide a means of configuring Standard Admininistrative-Group
+(RFC3630, RFC5305 and RFC5329) and Extended Admininistrative-Group (RFC7308).
+An affinity-map maps a specific bit position to a human readable-name.
+
+An affinity refers to a color or a ressource class in the Traffic Engineering
+terminology. The bit position means the position of the bit set starting from
+the least significant bit. For example, if the affinity 'blue' has bit position
+0 the extended Admin-Group value will be 0x01. If the affinity 'red' bit
+position 2 was added to a link in combination with the 'blue' affinity, the
+Admin-Group value would be 0x05.
+
+Command
+-------
+
+.. clicmd:: affinity-map NAME bit-position (0-1023)
+
+   Map the affinity name NAME to the bit-position. The bit-position is the key
+   so that only one name can be mapped to particular bit-position.
+
+.. clicmd:: no affinity-map NAME
+
+   Remove the affinity-map mapping.
+
+Affinity-maps with a bit-position value higher than 31 are not compatible with
+Standard Admininistrative-Group. The CLI disallow the usage of such
+affinity-maps when Standard Admininistrative-Groups are required.
\ No newline at end of file
diff --git a/doc/user/subdir.am b/doc/user/subdir.am
index 706e1ea449..b8c5c70d9c 100644
--- a/doc/user/subdir.am
+++ b/doc/user/subdir.am
@@ -3,6 +3,7 @@
 #
 
 user_RSTFILES = \
+	doc/user/affinitymap.rst \
 	doc/user/babeld.rst \
 	doc/user/ldpd.rst \
 	doc/user/basic.rst \
diff --git a/doc/user/zebra.rst b/doc/user/zebra.rst
index c05a29af4e..7d61cb3860 100644
--- a/doc/user/zebra.rst
+++ b/doc/user/zebra.rst
@@ -222,8 +222,6 @@ Link Parameters Commands
 
 .. clicmd:: unrsv-bw (0-7) BANDWIDTH
 
-.. clicmd:: admin-grp BANDWIDTH
-
    These commands specifies the Traffic Engineering parameters of the interface
    in conformity to RFC3630 (OSPF) or RFC5305 (ISIS).  There are respectively
    the TE Metric (different from the OSPF or ISIS metric), Maximum Bandwidth
@@ -234,6 +232,36 @@ Link Parameters Commands
    Note that BANDWIDTH is specified in IEEE floating point format and express
    in Bytes/second.
 
+.. clicmd:: admin-grp 0x(0-FFFFFFFF)
+
+   This commands configures the Traffic Engineering Admin-Group of the interface
+   as specified in RFC3630 (OSPF) or RFC5305 (ISIS). Admin-group is also known
+   as Resource Class/Color in the OSPF protocol.
+
+.. clicmd:: [no] affinity AFFINITY-MAP-NAME
+
+   This commands configures the Traffic Engineering Admin-Group of the
+   interface using the affinity-map definitions (:ref:`affinity-map`).
+   Multiple AFFINITY-MAP-NAME can be specified at the same time. Affinity-map
+   names are added or removed if ``no`` is present. It means that specifying one
+   value does not override the full list.
+
+   ``admin-grp`` and ``affinity`` commands provide two ways of setting
+   admin-groups. They cannot be both set on the same interface.
+
+.. clicmd:: [no] affinity-mode [extended|standard|both]
+
+   This commands configures which admin-group format is set by the affinity
+   command. ``extended`` Admin-Group is the default and uses the RFC7308 format.
+   ``standard`` mode uses the standard admin-group format that is defined by
+   RFC3630, RFC5305 and RFC5329. When the ``standard`` mode is set,
+   affinity-maps with bit-positions higher than 31 cannot be applied to the
+   interface. The ``both`` mode allows setting standard and extended admin-group
+   on the link at the same time. In   this case, the bit-positions 0 to 31 are
+   the same on standard and extended admin-groups.
+
+   Note that extended admin-groups are only supported by IS-IS for the moment.
+
 .. clicmd:: delay (0-16777215) [min (0-16777215) | max (0-16777215)]
 
 .. clicmd:: delay-variation (0-16777215)