Added healthcheck that checks if network is still up

Dockerfile

@@ -34,11 +34,14 @@ RUN apt-get update \
     && apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* \
     && groupmod -g 1000 users \
     && useradd -u 911 -U -d /config -s /bin/false abc \
-    && usermod -G users abc
+    && usermod -G users abc \
 
 ADD openvpn/ /etc/openvpn/
 ADD transmission/ /etc/transmission/
 ADD tinyproxy /opt/tinyproxy/
+ADD scripts /etc/scripts/
+
+RUN chmod a+x /etc/scripts/healthcheck.sh
 
 ENV OPENVPN_USERNAME=**None** \
     OPENVPN_PASSWORD=**None** \
@@ -129,7 +132,10 @@ ENV OPENVPN_USERNAME=**None** \
     TRANSMISSION_WEB_HOME= \
     DROP_DEFAULT_ROUTE= \
     WEBPROXY_ENABLED=false \
-    WEBPROXY_PORT=8888
+    WEBPROXY_PORT=8888 \
+    HEALTH_CHECK_HOST=google.com
+
+HEALTHCHECK --interval=5m CMD /etc/scripts/healthcheck.sh
 
 # Expose port and run
 EXPOSE 9091

scripts/healthcheck.sh

@@ -0,0 +1,22 @@
+#!/bin/sh
+# Ping uses both exit codes 1 and 2. Exit code 2 cannot be used for docker health checks,
+# therefore we use this script to catch error code 2
+HOST=$HEALTH_CHECK_HOST
+
+if [ -z "$HOST" ]
+then
+    echo "Host  not set! Set env 'HEATH_CHECK_HOST'. For now, using default google.com"
+    HOST="google.com"
+fi
+
+ping -c 1 $HOST
+STATUS=$?
+if [ $STATUS -ne 0 ]
+then
+    echo "Network is down"
+    exit 1
+fi
+
+echo "Network is up"
+exit 0
+