diff --git a/setup/so-functions b/setup/so-functions
index 8a5416e3d..db3973c27 100755
--- a/setup/so-functions
+++ b/setup/so-functions
@@ -245,7 +245,7 @@ collect_dns() {
 collect_dns_domain() {
 	whiptail_management_interface_dns_search "searchdomain.local"
 
-	while ! valid_ip4 "$DOCKERNET" || [[ $DOCKERNET =~ "172.17.0." ]]; do
+	while ! valid_fqdn "$MSEARCH"; do
 		whiptail_invalid_input
 		whiptail_management_interface_dns_search "$MSEARCH"
 	done
@@ -255,7 +255,7 @@ collect_dockernet() {
 	if ! whiptail_dockernet_check; then
 		whiptail_dockernet_sosnet "172.17.1.0"
 
-		while ! valid_ip4 "$DOCKERNET"; do
+		while ! valid_ip4 "$DOCKERNET" || [[ $DOCKERNET =~ "172.17.0." ]]
 			whiptail_invalid_input
 			whiptail_dockernet_sosnet "$DOCKERNET"
 		done