diff --git a/templates/keepalived-checks.j2 b/templates/keepalived-checks.j2
index f6b61cb..b2ab777 100644
--- a/templates/keepalived-checks.j2
+++ b/templates/keepalived-checks.j2
@@ -2,7 +2,9 @@
     {% if rserver.tcp_checks is defined %}
     {% for tcp_check in rserver.tcp_checks %}
     TCP_CHECK {
+      {% if tcp_check.connect_port is defined and tcp_check.connect_port %}
       connect_port {{ tcp_check.connect_port }}
+      {% endif %}
       connect_timeout {{ tcp_check.connect_timeout | default('5') }}
       {% if tcp_check.connect_ip is defined and tcp_check.connect_ip %}
       connect_ip {{ tcp_check.connect_ip }}
diff --git a/templates/keepalived-virtual-server.j2 b/templates/keepalived-virtual-server.j2
index c13ddd6..16b2cb3 100644
--- a/templates/keepalived-virtual-server.j2
+++ b/templates/keepalived-virtual-server.j2
@@ -1,10 +1,15 @@
 {# extra spaces are needed for backward compatibility #}
-  ip_family {{ vserver.ip_family | default('inet') }}
+  {% if vserver.ip_family is defined %}
+  ip_family {{ vserver.ip_family | default('inet', true) }}
+  {% endif %}
   {% if vserver.delay_loop is defined %}
   delay_loop {{ vserver.delay_loop }}
   {% endif %}
   lvs_sched {{ vserver.lvs_sched | default ('rr') }}
   lvs_method {{ vserver.lvs_method | default ('DR') }}
+  {% if vserver.persistence_timeout is defined %}
+  persistence_timeout {{ vserver.persistence_timeout }}
+  {% endif %}
   protocol {{ vserver.protocol | default ('TCP') }}
   {% if vserver.ha_suspend is defined and vserver.ha_suspend %}
   ha_suspend