diff --git a/includes/site.h b/includes/site.h
index 018f6838..7ef206d2 100644
--- a/includes/site.h
+++ b/includes/site.h
@@ -48,6 +48,21 @@
 
 /* #define POINTER_DEBUG */
 
+/* Define this if you want debugging output for DHCP failover protocol
+   messages. */
+
+/* #define DEBUG_FAILOVER_MESSAGES */
+
+/* Define this if you want debugging output for DHCP failover protocol
+   lease assignment timing. */
+
+/* #define DEBUG_FAILOVER_TIMING */
+
+/* Define this if you want DHCP failover protocol support in the DHCP
+   server. */
+
+/* #define FAILOVER_PROTOCOL */
+
 /* Define this if you want the dhcpd.pid file to go somewhere other than
    the default (which varies from system to system, but is usually either
    /etc or /var/run. */