diff --git a/demo_lxc_build.sh b/demo_lxc_build.sh
index 7811351..02b215c 100755
--- a/demo_lxc_build.sh
+++ b/demo_lxc_build.sh
@@ -152,21 +152,21 @@ fi
 ynh_print_info --message="> Creating a snapshot for $lxc_name1" | tee -a "$LOG_BUILD_LXC" 2>&1
 ynh_lxc_create_snapshot --name="$lxc_name1" --snapname="snap0"
 
-ynh_print_info --message="> Upgrading the $lxc_name1" | tee -a "$LOG_BUILD_LXC" 2>&1
+ynh_print_info --message="> Upgrading the $lxc_name1 LXC container" | tee -a "$LOG_BUILD_LXC" 2>&1
 ynh_lxc_stop --name="$lxc_name1" | tee -a "$LOG_BUILD_LXC" 2>&1
-ynh_lxc_upgrade_demo --name=$lxc_name1 --time_to_switch=$time_to_switch
+ynh_lxc_upgrade_demo --name=$lxc_name1 --time_to_switch=$time_to_switch | tee -a "$LOG_BUILD_LXC" 2>&1
 
 ynh_print_info --message="> Cloning $lxc_name1 to $lxc_name2" | tee -a "$LOG_BUILD_LXC" 2>&1
 ynh_lxc_clone --source="$lxc_name1" --destination="$lxc_name2" | tee -a "$LOG_BUILD_LXC" 2>&1
 
 ynh_print_info --message="> Creating a snapshot for $lxc_name2" | tee -a "$LOG_BUILD_LXC" 2>&1
-ynh_lxc_create_snapshot --name="$lxc_name2" --snapname="snap0"
+ynh_lxc_create_snapshot --name="$lxc_name2" --snapname="snap0" | tee -a "$LOG_BUILD_LXC" 2>&1
 
 ynh_print_info --message="> Setuping the switch cron" | tee -a "$LOG_BUILD_LXC" 2>&1
-ynh_add_config --template="$final_path/conf/cron_demo_switch" --destination="/etc/cron.d/demo_switch"
+ynh_add_config --template="$final_path/conf/cron_demo_switch" --destination="/etc/cron.d/demo_switch" | tee -a "$LOG_BUILD_LXC" 2>&1
 
 ynh_print_info --message="> and the upgrade cron" | tee -a "$LOG_BUILD_LXC" 2>&1
-ynh_add_config --template="$final_path/conf/cron_demo_upgrade" --destination="/etc/cron.d/demo_upgrade"
+ynh_add_config --template="$final_path/conf/cron_demo_upgrade" --destination="/etc/cron.d/demo_upgrade" | tee -a "$LOG_BUILD_LXC" 2>&1
 
 ynh_print_info --message="> Setuping the service" | tee -a "$LOG_BUILD_LXC" 2>&1
 #ynh_add_systemd_config --template="$final_path/conf/systemd.service"
diff --git a/demo_lxc_destroy.sh b/demo_lxc_destroy.sh
index 889792e..9e265d8 100755
--- a/demo_lxc_destroy.sh
+++ b/demo_lxc_destroy.sh
@@ -22,9 +22,9 @@ ynh_print_info --message=">> Starting demo destroy."
 /bin/bash "$final_path/demo_stop.sh" -f
 
 ynh_print_info --message="> Deleting containers and snapshots"
-ynh_secure_remove --file="/var/lib/lxd/snapshots/$lxc_name1/snap0.tar.gz"
+ynh_exec_warn_less ynh_secure_remove --file="/var/lib/lxd/snapshots/$lxc_name1/snap0.tar.gz"
 ynh_lxc_delete --name=$lxc_name1
-ynh_secure_remove --file="/var/lib/lxd/snapshots/$lxc_name2/snap0.tar.gz"
+ynh_exec_warn_less ynh_secure_remove --file="/var/lib/lxd/snapshots/$lxc_name2/snap0.tar.gz"
 ynh_lxc_delete --name=$lxc_name2
 
 ynh_print_info --message="> Deleting crons"
diff --git a/demo_stop.sh b/demo_stop.sh
index f5b2024..c9d9b20 100755
--- a/demo_stop.sh
+++ b/demo_stop.sh
@@ -20,10 +20,10 @@ ynh_print_info --message=">> Stopping demo." | tee -a "$final_path/demo_boot.log
 if [ "$#" -eq 1 ] && [ "$1" == "-f" ]
 then
 	ynh_print_info --message="> Deleting locks and force stopping LXC containers." | tee -a "$final_path/demo_boot.log" 2>&1
-	ynh_secure_remove --file="/var/lib/lxd/$lxc_name1.lock_fileS"
-	ynh_secure_remove --file="/var/lib/lxd/$lxc_name2.lock_fileS"
-	ynh_secure_remove --file="/var/lib/lxd/$lxc_name1.lock_fileU"
-	ynh_secure_remove --file="/var/lib/lxd/$lxc_name2.lock_fileU"
+	ynh_exec_warn_less ynh_secure_remove --file="/var/lib/lxd/$lxc_name1.lock_fileS"
+	ynh_exec_warn_less ynh_secure_remove --file="/var/lib/lxd/$lxc_name2.lock_fileS"
+	ynh_exec_warn_less ynh_secure_remove --file="/var/lib/lxd/$lxc_name1.lock_fileU"
+	ynh_exec_warn_less ynh_secure_remove --file="/var/lib/lxd/$lxc_name2.lock_fileU"
 else
 	ynh_print_info --message="> Waiting locks." | tee -a "$final_path/demo_boot.log" 2>&1
 	while test -e /var/lib/lxd/$lxc_name1.lock_file* || test -e /var/lib/lxd/$lxc_name2.lock_file*; do
diff --git a/ynh_lxd_demo b/ynh_lxd_demo
index e16b3c3..51a99db 100644
--- a/ynh_lxd_demo
+++ b/ynh_lxd_demo
@@ -157,7 +157,7 @@ ynh_lxc_upgrade_demo() {
 	if [ "$update_apt" -eq "1" ]
 	then
 		# Archivage du snapshot
-		tar -cz --acls --xattrs -f /var/lib/lxd/snapshots/$name/snap0.tar.gz /var/lib/lxd/snapshots/$name/snap0
+		ynh_exec_warn_less tar -cz --acls --xattrs -f /var/lib/lxd/snapshots/$name/snap0.tar.gz /var/lib/lxd/snapshots/$name/snap0
 		# Remplacement du snapshot
 		ynh_lxc_create_snapshot --name=$name --snapname=snap0