doc: Explaining that bgpd can listen on multiple addresses

Updated the documentation clarifying that multiple addresses can be
specifyed via -l option.

Signed-off-by: "Adriano Marto Reis" <adrianomarto@gmail.com>

diff --git a/doc/user/bgp.rst b/doc/user/bgp.rst
index 7bef7d19c8ba3a300238a41a65155de86c11764e..a49c2602645e73ab20d820347144df4ad5542b27 100644 (file)
--- a/doc/user/bgp.rst
+++ b/doc/user/bgp.rst
@@ -31,12 +31,23 @@ be specified (:ref:`common-invocation-options`).
 
 .. option:: -l, --listenon
 
-   Specify a specific IP address for bgpd to listen on, rather than its default
+   Specify specific IP addresses 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.
+   address, or to run multiple bgpd processes on one host. Multiple addresses
+   can be specified.
+
+   In the following example, bgpd is started listening for connections on the
+   addresses 100.0.1.2 and fd00::2:2. The options -d (runs in daemon mode) and
+   -f (uses specific configuration file) are also used in this example as we
+   are likely to run multiple bgpd instances, each one with different
+   configurations, when using -l option.
 
    Note that this option implies the --no_kernel option, and no learned routes will be installed into the linux kernel.
 
+.. code-block:: shell
+
+   # /usr/lib/frr/bgpd -d -f /some-folder/bgpd.conf -l 100.0.1.2 -l fd00::2:2
+
 .. option:: -n, --no_kernel
 
    Do not install learned routes into the linux kernel.  This option is useful