A simple shell script that obtains de IP from all the instances of ElasticBeanstalk apps/envs and adds them to the /etc/hosts of a server.

get_ebenvs_ips.sh

#!/bin/sh
####################################################
# por: Christian Dechery
# objetivo: obtem os enderecos IP de todas as instancias de aplicacoes
#           rodando no ElasticBeanstalk
###################################################

envs=("tecvirt" "hmlg" "mock" "hmlg2" "prod")
cat base_hosts > new_hosts

for env in ${envs[@]}; do
    envinfo=`aws elasticbeanstalk describe-environment-resources --environment-name ${env} | jq '.EnvironmentResources| .Instances[]' | grep "Id"`

    i=1
    while read -r line; do
        instanceid=`echo $line | awk -F ':' '{print $2}' | tr -d '"'`
        ip=`aws ec2 describe-instances --instance-ids ${instanceid} | jq -r '.Reservations[].Instances[].NetworkInterfaces[].PrivateIpAddress'`
        echo "$ip       $env-$i" >> new_hosts
        ((i+=1))
    done <<< "$envinfo"
done

sudo sh -c 'cat new_hosts > /etc/hosts'
rm new_hosts