From efc78f0db66d3851ab1db4e24011b9e596990165 Mon Sep 17 00:00:00 2001
From: "Dustin C. Hatch" <dustin@hatch.name>
Date: Sun, 6 May 2018 13:38:15 -0500
Subject: [PATCH] roles/dhcpd: Allow disabling DDNS per-subnet

In some cases, DDNS may be enabled globally, but some subnets may not
utilize it. To support this scenario, subnets can set `ddns_updates` to
false.
---
 roles/dhcpd/templates/dhcpd.conf.j2 | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/roles/dhcpd/templates/dhcpd.conf.j2 b/roles/dhcpd/templates/dhcpd.conf.j2
index 1b57821..ab46ea8 100644
--- a/roles/dhcpd/templates/dhcpd.conf.j2
+++ b/roles/dhcpd/templates/dhcpd.conf.j2
@@ -50,7 +50,9 @@ subnet {{ subnet.address|ipv4('network') }} netmask {{ subnet.address|ipv4('netm
     filename "{{ subnet.boot_filename }}";
 {% endif %}
 {% endif %}
-{% if subnet.dynamic_hostnames|d|bool %}
+{% if not subnet.ddns_updates|d(true)|bool %}
+    ddns-updates off;
+{% elif subnet.dynamic_hostnames|d|bool %}
     option host-name = {{ dyn_hostname_expr.format(prefix=subnet.dyn_hostname_prefix|d(default_dyn_hostname_prefix)) }};
     ddns-hostname = {{ dyn_hostname_expr.format(prefix=subnet.dyn_hostname_prefix|d(default_dyn_hostname_prefix)) }};
 {% endif %}