diff --git a/net/frr/src/opnsense/mvc/app/controllers/OPNsense/Quagga/forms/dialogEditOSPFInterface.xml b/net/frr/src/opnsense/mvc/app/controllers/OPNsense/Quagga/forms/dialogEditOSPFInterface.xml
index b7091f4f0..1413f214f 100644
--- a/net/frr/src/opnsense/mvc/app/controllers/OPNsense/Quagga/forms/dialogEditOSPFInterface.xml
+++ b/net/frr/src/opnsense/mvc/app/controllers/OPNsense/Quagga/forms/dialogEditOSPFInterface.xml
@@ -37,6 +37,18 @@
     <label>Cost</label>
     <type>text</type>
   </field>
+  <field>
+    <id>interface.cost_demoted</id>
+    <label>Cost (when demoted)</label>
+    <type>text</type>
+  </field>
+  <field>
+    <id>interface.carp_depend_on</id>
+    <label>Depend on (carp)</label>
+    <type>dropdown</type>
+    <help>The carp VHID to depend on, when this virtual address is not in master state,
+      the interface cost will be set to the demoted cost (specified above).</help>
+  </field>
   <field>
     <id>interface.hellointerval</id>
     <label>Hello Interval</label>
diff --git a/net/frr/src/opnsense/mvc/app/models/OPNsense/Quagga/OSPF.xml b/net/frr/src/opnsense/mvc/app/models/OPNsense/Quagga/OSPF.xml
index ef022849a..445f2786a 100644
--- a/net/frr/src/opnsense/mvc/app/models/OPNsense/Quagga/OSPF.xml
+++ b/net/frr/src/opnsense/mvc/app/models/OPNsense/Quagga/OSPF.xml
@@ -165,6 +165,17 @@
                                 <MaximumValue>4294967295</MaximumValue>
                                 <ValidationMessage>Cost must be between 0 and 4294967295.</ValidationMessage>
                         </cost>
+                        <cost_demoted type="IntegerField">
+                                <default></default>
+                                <MinimumValue>0</MinimumValue>
+                                <Required>N</Required>
+                                <MaximumValue>4294967295</MaximumValue>
+                                <ValidationMessage>Cost must be between 0 and 4294967295.</ValidationMessage>
+                        </cost_demoted>
+                        <carp_depend_on type="VirtualIPField">
+                            <type>carp</type>
+                            <Required>N</Required>
+                        </carp_depend_on>
                         <hellointerval type="IntegerField">
                                 <default></default>
                                 <MinimumValue>0</MinimumValue>
diff --git a/net/frr/src/opnsense/service/templates/OPNsense/Quagga/+TARGETS b/net/frr/src/opnsense/service/templates/OPNsense/Quagga/+TARGETS
index b01f28018..a09b88d86 100644
--- a/net/frr/src/opnsense/service/templates/OPNsense/Quagga/+TARGETS
+++ b/net/frr/src/opnsense/service/templates/OPNsense/Quagga/+TARGETS
@@ -1,5 +1,6 @@
 bgpd.conf:/usr/local/etc/frr/bgpd.conf
 ospfd.conf:/usr/local/etc/frr/ospfd.conf
+ospfd_carp.conf:/usr/local/etc/frr/ospfd_carp.conf
 ospf6d.conf:/usr/local/etc/frr/ospf6d.conf
 ripd.conf:/usr/local/etc/frr/ripd.conf
 frr:/etc/rc.conf.d/frr
diff --git a/net/frr/src/opnsense/service/templates/OPNsense/Quagga/ospfd_carp.conf b/net/frr/src/opnsense/service/templates/OPNsense/Quagga/ospfd_carp.conf
new file mode 100644
index 000000000..90e2149e2
--- /dev/null
+++ b/net/frr/src/opnsense/service/templates/OPNsense/Quagga/ospfd_carp.conf
@@ -0,0 +1,11 @@
+{% if helpers.exists('OPNsense.quagga.ospf.interfaces.interface') %}
+{%   for interface in helpers.toList('OPNsense.quagga.ospf.interfaces.interface') %}
+{%     if interface.enabled == '1' %}
+[interface_interface.interfacename]
+interface={{interface.interfacename}}
+default_cost={{interface.cost|default('10')}}
+demoted_cost={{interface.cost_demoted|default('')}}
+carp_depend_on={{interface.carp_depend_on|default('')}}
+{%     endif %}
+{%   endfor %}
+{% endif %}