clustering: remove broken/unmaintained features

Could be readded in the future with e.g. pacemaker/corosync.

docs/clustering.rst

@@ -1,76 +0,0 @@
-.. _clustering:
-
-Clustering
-==========
-
-The cluster feature allows 2 vyos routers to share IP addresses and various services.
-
-VyOS supports multicast clustering.
-
-.. note::
-  Please follow the process of the cluster function here. https://phabricator.vyos.net/T985
-
-
-General cluster configuration
------------------------------
-
-In the general cluster configuration the network interfaces used for monitoring and negotiation of the cluster health is defined.
-Additionally, the communication interval settings, multicast group (for sending/receiving heartbeat messages), and pre-shared secret used in this monitoring is defined.
-
-.. code-block:: none
-
-  vyos@vyos# set cluster
-  Possible completions:
-    dead-interval            Interval after which a node is considered dead after missing heartbeats (milliseconds)
-  +> group                   Name of resource group for clustering [REQUIRED]
-  +  interface               Interface(s) for sending/receiving heartbeat packets [REQUIRED]
-    keepalive-interval       Time interval between heartbeat packets (milliseconds)
-    mcast-group              Multicast group for sending/receiving heartbeat packets
-    monitor-dead-interval    Interval after which a monitor node is considered dead (milliseconds)
-    pre-shared-secret        Pre-shared secret for authentication between cluster nodes [REQUIRED]
-
-Cluster group configuration
----------------------------
-
-For the cluster group configuration, the group name must be defined before the groups configuration can be set (See Example below).
-After the group name is defined, the specific service to be clustered between primary and secondary nodes is configured.
-
-.. code-block:: none
-
-  vyos@vyos# set cluster group GROUPNAME
-  Possible completions:
-    auto-failback        Fail back to primary node if it recovers from failure
-  +  monitor             IP address(es) for monitoring connectivity
-    primary              Host name of the primary node [REQUIRED]
-  +  secondary           Host name(s) of the secondary node(s) [REQUIRED]
-  +  service             IP address(es) or service name(s) in this resource group [REQUIRED]
-
-Review cluster status
----------------------
-
-.. code-block:: none
-
-  vyos@vyos:~$ show cluster status
-
-
-Example
--------
-
-In the example below SSH is clustered between two nodes.
-
-.. code-block:: none
-
-  cluster {
-      dead-interval 20000
-      group cluster {
-          auto-failback false
-          primary node1
-          secondary node2
-          service ssh
-          service 192.168.0.123/24/eth0
-      }
-      interface eth0
-      keepalive-interval 5000
-      monitor-dead-interval 20000
-      pre-shared-secret S3cr#t
-  }

docs/index.rst

@@ -40,7 +40,6 @@ VyOS User Guide
    qos
    high-availability
    vpn/index
-   clustering
    load-balancing
    commandscripting
    troubleshooting
@@ -88,4 +87,5 @@ to this one.
 Permission is granted to copy and distribute translations of this manual into
 another language, under the above conditions for modified versions, except that
 this permission notice may be stated in a translation approved by the VyOS
-maintainers.
+maintainers.
+