Adding reference to EXTERNAL_NETWORK to user guide

Adding a reference to the EXTERNAL_NETWORK environment variable to the
user guide so that users add this to their env_config.sh. This variable
is required, among others, to overwrite the default external network in
Yarstick.

Change-Id: I50e609a8c6e20b1dd01c61d5d950ffba792e98fa
Signed-off-by: Georg Kunz <georg.kunz@ericsson.com>

diff --git a/docs/testing/user/userguide/testing_guide.rst b/docs/testing/user/userguide/testing_guide.rst
index e5462b3..e843060 100644 (file)
--- a/docs/testing/user/userguide/testing_guide.rst
+++ b/docs/testing/user/userguide/testing_guide.rst
@@ -226,8 +226,11 @@ this file should contain.
    # If using https + no cacert, should add OS_INSECURE environment parameter.
    export OS_INSECURE=True
 
-   # External network name for allocating floating IPs.
-   # The attribute 'external' for this network must be True.
+   # The name of a network with external connectivity for allocating floating
+   # IPs. It is required that at least one Neutron network with the attribute
+   # 'router:external=True' is pre-configured on the system under test.
+   # This network is used by test cases to SSH into tenant VMs and perform
+   # operations there.
    export EXTERNAL_NETWORK=xxx