diff --git a/lib.nix b/lib.nix
index b4b47a4..97a0e48 100644
--- a/lib.nix
+++ b/lib.nix
@@ -19,8 +19,12 @@ let
       hostNetwork = entities.zones."${hostDomain}";
     in hostNetwork.hosts."${hostname}";
 
-  getHostIpv4 = hostname: (getHostNetworkSettings hostname).ipv4-address;
-  getHostIpv6 = hostname: (getHostNetworkSettings hostname).ipv6-address;
+  getIfAttr = as: a: if hasAttr as a then getAttr as a else null;
+
+  getHostIpv4 = hostname:
+    getIfAttr (getHostNetworkSettings hostname) "ipv4-address";
+  getHostIpv6 = hostname:
+    getIfAttr (getHostNetworkSettings hostname) "ipv6-address";
   getHostIps = hostname:
     filter (o: o != null) [ (getHostIpv4 hostname) (getHostIpv6 hostname) ];