diff --git a/Dockerfile b/Dockerfile
index 8ba1496..7f7ccf2 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -6,6 +6,7 @@ ARG DEBIAN_FRONTEND noninteractive
 RUN apt-get update && apt-get -y upgrade && \
 	apt-get --no-install-recommends -y install \
 	wget \
+	procps \
 	iptables \
 	iproute2 \
 	dnsmasq \
diff --git a/run/network.sh b/run/network.sh
index 4a68011..919e19e 100644
--- a/run/network.sh
+++ b/run/network.sh
@@ -183,7 +183,7 @@ if [ ! -c /dev/net/tun ]; then
   chmod 666 /dev/net/tun
 fi
 
-[ ! -c /dev/net/tun ] && echo "Error: TUN network interface not available..." && exit 85
+[ ! -c /dev/net/tun ] && echo "ERROR: TUN network interface not available..." && exit 85
 
 update-alternatives --set iptables /usr/sbin/iptables-legacy > /dev/null
 update-alternatives --set ip6tables /usr/sbin/ip6tables-legacy > /dev/null