doc: Add cli options for bgp to documentation

Document the bgp cli options.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>

doc/manpages/bgpd.rst

@@ -21,6 +21,48 @@ OPTIONS available for the |DAEMON| command:
 
 .. include:: common-options.rst
 
+.. option:: -p, --bgp_port <port>
+
+   Set the bgp protocol's port number. When port number is 0, that means do not
+   listen bgp port.
+
+.. option:: -l, --listenon
+
+   Specify a specific IP address for bgpd to listen on, rather than its default
+   of ``0.0.0.0`` / ``::``. This can be useful to constrain bgpd to an internal
+   address, or to run multiple bgpd processes on one host.
+
+.. option:: -n, --no_kernel
+
+   Do not install learned routes into the linux kernel.  This option is useful
+   for a route-reflector environment or if you are running multiple bgp
+   processes in the same namespace.  This option is different than the --no_zebra
+   option in that a ZAPI connection is made.
+
+.. option:: -S, --skip_runas
+
+   Skip the normal process of checking capabilities and changing user and group
+   information.
+
+.. option:: -e, --ecmp
+
+   Run BGP with a limited ecmp capability, that is different than what BGP
+   was compiled with.  The value specified must be greater than 0 and less
+   than or equal to the MULTIPATH_NUM specified on compilation.
+
+.. option:: -Z, --no_zebra
+
+   Do not communicate with zebra at all.  This is different than the --no_kernel
+   option in that we do not even open a ZAPI connection to the zebra process.
+
+.. option:: -s, --socket_size
+
+   When opening tcp connections to our peers, set the socket send buffer
+   size that the kernel will use for the peers socket.  This option
+   is only really useful at a very large scale.  Experimentation should
+   be done to see if this is helping or not at the scale you are running
+   at.
+
 LABEL MANAGER
 -------------
 

doc/user/bgp.rst

@@ -35,6 +35,44 @@ be specified (:ref:`common-invocation-options`).
    of ``0.0.0.0`` / ``::``. This can be useful to constrain bgpd to an internal
    address, or to run multiple bgpd processes on one host.
 
+.. option:: -n, --no_kernel
+
+   Do not install learned routes into the linux kernel.  This option is useful
+   for a route-reflector environment or if you are running multiple bgp
+   processes in the same namespace.  This option is different than the --no_zebra
+   option in that a ZAPI connection is made.
+
+.. option:: -S, --skip_runas
+
+   Skip the normal process of checking capabilities and changing user and group
+   information.
+
+.. option:: -e, --ecmp
+
+   Run BGP with a limited ecmp capability, that is different than what BGP
+   was compiled with.  The value specified must be greater than 0 and less
+   than or equal to the MULTIPATH_NUM specified on compilation.
+
+.. option:: -Z, --no_zebra
+
+   Do not communicate with zebra at all.  This is different than the --no_kernel
+   option in that we do not even open a ZAPI connection to the zebra process.
+
+.. option:: -s, --socket_size
+
+   When opening tcp connections to our peers, set the socket send buffer
+   size that the kernel will use for the peers socket.  This option
+   is only really useful at a very large scale.  Experimentation should
+   be done to see if this is helping or not at the scale you are running
+   at.
+
+LABEL MANAGER
+-------------
+
+.. option:: -I, --int_num
+
+   Set zclient id. This is required when using Zebra label manager in proxy mode.
+
 .. _bgp-basic-concepts:
 
 Basic Concepts