[spp] [PATCH v2 8/8] docs: revise how to use section of spp_vf

[ogawa.yasufumi at lab.ntt.co.jp]

From: Yasufumi Ogawa <ogawa.yasufumi at lab.ntt.co.jp>

Update launching SPP Controller still remained old.

Signed-off-by: Yasufumi Ogawa <ogawa.yasufumi at lab.ntt.co.jp>
---
 docs/guides/spp_vf/gsg/howto_use.rst | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/docs/guides/spp_vf/gsg/howto_use.rst b/docs/guides/spp_vf/gsg/howto_use.rst
index 44bc77a..750de13 100644
--- a/docs/guides/spp_vf/gsg/howto_use.rst
+++ b/docs/guides/spp_vf/gsg/howto_use.rst
@@ -9,11 +9,23 @@ How to Use
 SPP Controller
 --------------
 
-First, run SPP Controller with port numbers for spp primary and secondary.
+Go to the SPP's directory first.
 
 .. code-block:: console
 
-    $ python ./src/spp_vf.py -p 5555 -s 6666
+    $ cd /path/to/spp
+
+Launch ``spp-ctl`` before launching SPP primary and secondary processes.
+You also need to launch ``spp.py``  if you use ``spp_vf`` from CLI.
+``-b`` option is for binding IP address to communicate other SPP processes,
+but no need to give it explicitly if ``127.0.0.1`` or ``localhost`` although
+doing explicitly in this example to be more understandable.
+
+.. code-block:: console
+
+    # Launch spp-ctl and spp.py
+    $ python3 ./src/spp-ctl/spp-ctl -b 127.0.0.1
+    $ python ./src/spp.py -b 127.0.0.1
 
 
 SPP Primary
-- 
2.7.4