Implement X.509 auth for MySQL and Neutron

Related-PROD: PROD-22796

Change-Id: Ib9fa1bd81455c346e56d2583959c7bae406ccd35
diff --git a/README.rst b/README.rst
index 4cc9fc1..620e100 100644
--- a/README.rst
+++ b/README.rst
@@ -1459,6 +1459,29 @@
 +-------------------------------+------------------------------------------------------+
 
 
+Enable x509 and ssl communication between Neutron and Galera cluster.
+---------------------
+By default communication between Neutron and Galera is unsecure.
+
+neutron:
+  server:
+    database:
+      x509:
+        enabled: True
+
+You able to set custom certificates in pillar:
+
+neutron:
+  server:
+    database:
+      x509:
+        cacert: (certificate content)
+        cert: (certificate content)
+        key: (certificate content)
+
+You can read more about it here:
+    https://docs.openstack.org/security-guide/databases/database-access-control.html
+
 Documentation and Bugs
 ======================