diff --git a/add.go b/add.go
index 736fb9b..711113e 100644
--- a/add.go
+++ b/add.go
@@ -19,7 +19,11 @@ DNS={{ .DsnetConfig.DNS }}
 [Peer]
 PublicKey={{ .DsnetConfig.PrivateKey.PublicKey.Key }}
 PresharedKey={{ .Peer.PresharedKey.Key }}
+{{ if gt (.DsnetConfig.ExternalIP | len) 0 -}}
 Endpoint={{ .DsnetConfig.ExternalIP }}:{{ .DsnetConfig.ListenPort }}
+{{ else -}}
+Endpoint={{ .DsnetConfig.ExternalIP6 }}:{{ .DsnetConfig.ListenPort }}
+{{ end -}}
 PersistentKeepalive={{ .Keepalive }}
 {{ with .DsnetConfig.Network -}}
 AllowedIPs={{ . }}
diff --git a/configtypes.go b/configtypes.go
index 21096d1..5688c08 100644
--- a/configtypes.go
+++ b/configtypes.go
@@ -36,7 +36,7 @@ type PeerConfig struct {
 type DsnetConfig struct {
 	// domain to append to hostnames. Relies on separate DNS server for
 	// resolution. Informational only.
-	ExternalIP    net.IP `validate:"required"`
+	ExternalIP    net.IP
 	ExternalIP6   net.IP
 	ListenPort    int    `validate:"gte=1024,lte=65535"`
 	Domain        string `validate:"required,gte=1,lte=255"`