diff --git a/conf/ynh-vpnclient b/conf/ynh-vpnclient
index 910e282..6c85fbd 100644
--- a/conf/ynh-vpnclient
+++ b/conf/ynh-vpnclient
@@ -129,6 +129,10 @@ start_openvpn() {
     [ "${ynh_server_proto}" == tcp ] && proto=tcp-client
   fi
 
+  # Unset firewall to let DNS and NTP resolution works
+  # Firewall is reset after vpn is mounted (more details on #1016)
+  unset_firewall
+
   sync_time
 
   cp /etc/openvpn/client.conf{.tpl,}
@@ -199,7 +203,7 @@ stop_openvpn() {
 
 sync_time() {
   systemctl stop ntp
-  ntpd -qg &> /dev/null
+  timeout 20 ntpd -qg &> /dev/null
   systemctl start ntp
 }
 
diff --git a/scripts/install b/scripts/install
index b7747be..1c49433 100644
--- a/scripts/install
+++ b/scripts/install
@@ -33,7 +33,7 @@ fi
 ynh_webpath_register vpnclient $domain $url_path || exit 1
 
 # Install packages
-packages='php5-fpm sipcalc dnsutils openvpn curl'
+packages='php5-fpm sipcalc dnsutils openvpn curl fake-hwclock'
 export DEBIAN_FRONTEND=noninteractive
 
 sudo apt-get --assume-yes --force-yes install ${packages}