diff --git a/public_services/gourichon_org/domain/Dockerfile b/public_services/gourichon_org/domain/Dockerfile
index a946bec..0b6eac7 100644
--- a/public_services/gourichon_org/domain/Dockerfile
+++ b/public_services/gourichon_org/domain/Dockerfile
@@ -1,7 +1,7 @@
 FROM debian:stable-slim
 MAINTAINER Stéphane Gourichon <stephane_sysadmin@gourichon.org>
 
-RUN export DEBIAN_FRONTEND=noninteractive ; apt-get update && apt-get upgrade
+RUN export DEBIAN_FRONTEND=noninteractive ; apt-get update && apt-get -y upgrade
 RUN export DEBIAN_FRONTEND=noninteractive ; apt-get install --no-install-recommends -y bind9
 
 COPY named.conf.local /etc/bind/
diff --git a/tools/containers_check_update_rebuild_switch.sh b/tools/containers_check_update_rebuild_switch.sh
index 9f2f5e3..ddfdd94 100755
--- a/tools/containers_check_update_rebuild_switch.sh
+++ b/tools/containers_check_update_rebuild_switch.sh
@@ -36,7 +36,7 @@ for CONTAINER_ID in "${CONTAINER_IDS[@]}"
 do
     echo "Processing $CONTAINER_ID"
     TMPFILE=$(mktemp)
-    docker exec -u root $CONTAINER_ID bash -c "export LC_ALL=C ; apt-get update ; apt-get upgrade --dry-run" | tee $TMPFILE
+    docker exec -u root $CONTAINER_ID bash -c "export LC_ALL=C ; apt-get update ; apt-get upgrade -y --dry-run" | tee $TMPFILE
     trap "rm $TMPFILE" EXIT
     if grep "0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded." $TMPFILE
     then