Semantic update of local address to private address and optimizations for slow connections.

cassandra-validation.yml

diff --git a/cassandra-validation.yml b/cassandra-validation.yml
index 130df3c..6c9ce47 100644
--- a/cassandra-validation.yml
+++ b/cassandra-validation.yml
@@ -36,7 +36,7 @@
 
   - name: Read cassandra schema
     become: yes
-    shell: "{{ cassandra_cli }} -h {{ local_address }} -f {{ schema_cql }}"
+    shell: "{{ cassandra_cli }} -h {{ private_address }} -f {{ schema_cql }}"
     tags: ['schema']
     register: schema