docker.userguide: Add note about 'python' dependency in multi node setup

Ansible needs python2 to be able to finish discovery on remote host
and on some distributions it may not be installed by default.

Added note about this dependency - 'python' package has to be
installed on each node in multi-node-setup.

Change-Id: I2741325a7b4b1b38bdfb1af427c65eeb90408aa6
Signed-off-by: Radoslaw Jablonski <radoslawx.jablonski@intel.com>

diff --git a/docs/release/userguide/docker.userguide.rst b/docs/release/userguide/docker.userguide.rst
index 6ba5af0..6064de2 100644 (file)
--- a/docs/release/userguide/docker.userguide.rst
+++ b/docs/release/userguide/docker.userguide.rst
@@ -182,6 +182,12 @@ To install Ansible 2.6.3 on Centos:
     $ sudo yum install python-pip
     $ sudo -H pip install 'ansible==2.6.3'
 
+.. note::
+   When using multi-node-setup, please make sure that 'python' package is
+   installed on all of the target nodes (ansible during 'Gathering facts'
+   phase is using python2 and it may not be installed by default on some
+   distributions - e.g. on Ubuntu 16.04 it has to be installed manually)
+
 Clone barometer repo
 ^^^^^^^^^^^^^^^^^^^^