diff --git a/misc/build.func b/misc/build.func
index ec9fa271fc..b4229305b0 100644
--- a/misc/build.func
+++ b/misc/build.func
@@ -241,8 +241,7 @@ PW="${PW##-password }"
 HN="${HN}"
 BRG="${BRG}"
 NET="${NET}"
-IPV6_METHOD="${IPV6_METHOD}"
-
+IPV6_METHOD="${IPV6_METHOD:-none}"
 # Set this only if using "IPV6_METHOD=static"
 #IPV6STATIC="fd00::1234/64"
 
@@ -279,7 +278,7 @@ PW="${PW##-password }"
 HN="${HN}"
 BRG="${BRG}"
 NET="${NET}"
-IPV6_METHOD="${IPV6_METHOD}"
+IPV6_METHOD="${IPV6_METHOD:-none}"
 
 # Set this only if using "IPV6_METHOD=static"
 #IPV6STATIC="fd00::1234/64"