get aws ELB instance IP addresses

get_elb_instance_ips.py

#!/usr/bin/env python

import boto
from boto.ec2 import elb


ACCESS_KEY_ID = 'access-key-id'
SECRET_ACCESS_KEY = 'secret-access-key'


def get_instances_ips(region, load_balancer_name):
    elb_conn = boto.ec2.elb.connect_to_region(region)
    ec2_connection = boto.ec2.connect_to_region(region)

    load_balancer = elb_conn.get_all_load_balancers(load_balancer_names=[load_balancer_name])[0]

    instance_ids = [ instance.id for instance in load_balancer.instances ]
    reservations = ec2_connection.get_all_instances(instance_ids)
    instance_addresses = [ i.ip_address for r in reservations for i in r.instances ]

    ips = []
    for r in reservations:
        for instance in r.instances:
            ips += [i.private_ip_addresses[0].private_ip_address for i in instance.interfaces]
    return ips


print 'IPs:', get_instances_ips('sa-east-1', 'foo')