diff --git a/lib/functions/rootfs/distro-agnostic.sh b/lib/functions/rootfs/distro-agnostic.sh
index 2302792a44..25ff64ea01 100644
--- a/lib/functions/rootfs/distro-agnostic.sh
+++ b/lib/functions/rootfs/distro-agnostic.sh
@@ -565,7 +565,7 @@ function install_distribution_agnostic() {
 	VENDORPRETTYNAME="$VENDORPRETTYNAME" >> "${SDCARD}"/etc/armbian-image-release
 
 	# DNS fix. package resolvconf is not available everywhere
-	if [ -d "${SDCARD}"/etc/resolvconf/resolv.conf.d ] && [ -n "$NAMESERVER" ]; then
+	if [[ -d "${SDCARD}/etc/resolvconf/resolv.conf.d" && -n "$NAMESERVER" ]]; then
 		echo "nameserver $NAMESERVER" > "${SDCARD}"/etc/resolvconf/resolv.conf.d/head
 	fi