diff --git a/pihole/bin/prepare_pd.sh b/pihole/bin/prepare_pd.sh
index 15b442c..195bf38 100755
--- a/pihole/bin/prepare_pd.sh
+++ b/pihole/bin/prepare_pd.sh
@@ -36,7 +36,10 @@ mkdir -p \
   "$APPDATA_PIHOLE_ROOT/etc-dnsmasq.d" \
   "$APPDATA_UNBOUND_ROOT/var"
 
-cp "$STACK_DIR/unbound.conf" "$APPDATA_UNBOUND_ROOT/unbound.conf"
+UNBOUND_TARGET="$APPDATA_UNBOUND_ROOT/unbound.conf"
+UNBOUND_TMP="$APPDATA_UNBOUND_ROOT/.unbound.conf.tmp.$$"
+cp "$STACK_DIR/unbound.conf" "$UNBOUND_TMP"
+mv -f "$UNBOUND_TMP" "$UNBOUND_TARGET"
 
 if [[ ! -s "$APPDATA_UNBOUND_ROOT/var/root.hints" ]]; then
   curl -fsSL -o "$APPDATA_UNBOUND_ROOT/var/root.hints" https://www.internic.net/domain/named.cache