Description of problem:
Can't successfully install undercloud on mitaka/newton on RHEL 7 unless the following patch is applied:

[root@undercloud-0-newton puppet-stack-config]# git diff -u puppet-stack-config.yaml.template.orig puppet-stack-config.yaml.template
diff --git a/puppet-stack-config.yaml.template.orig b/puppet-stack-config.yaml.template
index 1642307..3d4dd8e 100644
--- a/puppet-stack-config.yaml.template.orig
+++ b/puppet-stack-config.yaml.template
@@ -13,8 +13,8 @@ ntp::servers:
 sysctl_settings:
   net.ipv4.ip_nonlocal_bind:
     value: 1
-  net.ipv6.ip_nonlocal_bind:
-    value: 1
+#  net.ipv6.ip_nonlocal_bind:
+#    value: 1
 
 # SSL
 tripleo::haproxy::service_certificate: {{UNDERCLOUD_SERVICE_CERTIFICATE}}


Version-Release number of selected component (if applicable):


How reproducible:
Always

Steps to Reproduce:
1. type "openstack undercloud install" and wait
2.
3.

Actual results:
Fails

Expected results:
Succeeds

Additional info:
Fails to set net.ipv6.ip_nonlocal_bind