[es] Port over Swarm compatible binding address lookup

elasticsearch/Dockerfile

@@ -14,7 +14,6 @@ COPY start /start
 EXPOSE 9200 9300
 
 ENV ES_HOME=/usr/share/elasticsearch-$ES_VERSION \
-    OPTS=-Dnetwork.host=_non_loopback_ \
     DEFAULT_ES_USER=elasticsearch
 
 RUN adduser -S -s /bin/sh $DEFAULT_ES_USER

elasticsearch/README.md

@@ -182,13 +182,14 @@ Using the Docker Compose file above, a value of `2` is appropriate when scaling
 
     docker-compose scale master=3
 
-## Auto transport/http discovery with Swarm Mode
+## Multiple Network Binding, such as Swarm Mode
 
-When using Docker Swarm mode (starting with 1.12), the overlay and ingress network interfaces are assigned
-multiple IP addresses. As a result, it creates confusion for the transport publish logic even when using
-the special value `_eth0_`.
+When using Docker Swarm mode the container is presented with multiple ethernet
+devices. By default, all global, routable IP addresses are configured for
+Elasticsearch to use as `network.host`.
 
-To resolve this, add
+That discovery can be overridden by providing a specific ethernet device name
+to `DISCOVER_TRANSPORT_IP` and/or `DISCOVER_HTTP_IP`, such as
 
     -e DISCOVER_TRANSPORT_IP=eth0
 

elasticsearch/start

@@ -26,12 +26,11 @@ discoverIpFromLink() {
   OPTS="$OPTS -Des.$mode.host=$ip"
 }
 
-if [ "$DISCOVER_TRANSPORT_IP" != "" ]; then
-  discoverIpFromLink $DISCOVER_TRANSPORT_IP transport
-fi
-if [ "$DISCOVER_HTTP_IP" != "" ]; then
-  discoverIpFromLink $DISCOVER_HTTP_IP http
-fi
+discoverAllGlobalIps() {
+  ips=`ipaddr show scope global|awk '$1 == "inet" { if (!match($2,"/32")) { gsub("/.*","",$2) ; addrs[length(addrs)] = $2 } } END { for (i in addrs) { if (i>0) printf "," ; printf addrs[i] } }'`
+  OPTS="$OPTS --network.host=$ips"
+}
+
 
 if [ -n "$CLUSTER" ]; then
   OPTS="$OPTS -Des.cluster.name=$CLUSTER"
@@ -98,6 +97,7 @@ else
   mkdir -p /conf/plugins
 fi
 
+discoverAllGlobalIps
 mkdir -p /conf/scripts
 
 echo "Starting Elasticsearch with the options $OPTS"