diff --git a/xos/tools/get_instance_ip.py b/xos/tools/get_instance_ip.py
index 1783b25..e8b5ee8 100644
--- a/xos/tools/get_instance_ip.py
+++ b/xos/tools/get_instance_ip.py
@@ -4,24 +4,22 @@
 import os
 import requests
 import sys
+from optparse import OptionParser
 
 from operator import itemgetter, attrgetter
 
-REST_API="http://alpha.opencloud.us:8000/xos/"
-
-NODES_API = REST_API + "nodes/"
-SLICES_API = REST_API + "slices/"
-INSTANCES_API = REST_API + "instances/"
-PORTS_API = REST_API + "ports/"
-
-opencloud_auth=("demo@onlab.us", "demo")
-
 def get_slice_id(slice_name):
-    r = requests.get(SLICES_API + "?name=%s" % slice_name, auth=opencloud_auth)
+    r = requests.get(SLICES_API + "?name=%s" % slice_name, auth=OPENCLOUD_AUTH)
+    if (r.status_code!=200):
+        print >> sys.stderr, "Error: Slice REST API failed"
+        sys.exit(-1)
     return r.json()[0]["id"]
 
 def get_node_id(host_name):
-     r = requests.get(NODES_API)
+     r = requests.get(NODES_API, auth=OPENCLOUD_AUTH)
+     if (r.status_code!=200):
+        print >> sys.stderr, "Error: Node REST API failed"
+        sys.exit(-1)
      nodes = r.json()
      for node in nodes:
          if node["name"].lower() == host_name.lower():
@@ -41,56 +39,83 @@
     else:
         query_string = ""
 
-    r = requests.get(INSTANCES_API + query_string, auth=opencloud_auth)
+    r = requests.get(INSTANCES_API + query_string, auth=OPENCLOUD_AUTH)
+    if (r.status_code!=200):
+        print >> sys.stderr, "Error: Instance REST API failed"
+        sys.exit(-1)
+    return r.json()
+
+def get_networks():
+    r = requests.get(NETWORKS_API, auth=OPENCLOUD_AUTH)
+    if (r.status_code!=200):
+        print >> sys.stderr, "Error: Network REST API failed"
+        sys.exit(-1)
     return r.json()
 
 def main():
-    global opencloud_auth
+    global OPENCLOUD_AUTH, REST_API, NODES_API, SLICES_API, INSTANCES_API, PORTS_API, NETWORKS_API
 
-    if len(sys.argv)!=5:
-        print >> sys.stderr, "syntax: get_instance_name.py <username>, <password>, <hostname> <slicename>"
+    parser = OptionParser(usage="get_instance_ip.py [options] <rest_hostname> <rest_port>", )
+
+    parser.add_option("-u", "--username", dest="username", help="XOS admin username", metavar="NAME", default="padmin@vicci.org")
+    parser.add_option("-p", "--password", dest="password", help="XOS admin password", metavar="PASSWORD", default="letmein")
+    parser.add_option("-n", "--node", dest="node", help="show instances on node", metavar="HOSTNAME", default=None)
+    parser.add_option("-s", "--slice", dest="slice", help="show instances in slice", metavar="SLICENAME", default=None)
+    parser.add_option("-N", "--network", dest="filter_network_name", help="filter network name", metavar="NAME", default=None)
+    parser.add_option("-b", "--brief", dest="brief", help="only display the IP, nothing else", action="store_true", default=False)
+
+    (options, args) = parser.parse_args(sys.argv[1:])
+
+    if len(args)!=2:
+        print >> sys.stderr, "syntax: get_instance_name.py [options] <rest_hostname> <rest_port>"
         sys.exit(-1)
 
-    username = sys.argv[1]
-    password = sys.argv[2]
-    hostname = sys.argv[3]
-    slice_name = sys.argv[4]
+    rest_hostname = args[0]
+    rest_port = args[1]
 
-    opencloud_auth=(username, password)
+    REST_API="http://%s:%s/api/core/" % (rest_hostname, rest_port)
 
-    slice_id = get_slice_id(slice_name)
-    node_id = get_node_id(hostname)
+    NODES_API = REST_API + "nodes/"
+    SLICES_API = REST_API + "slices/"
+    INSTANCES_API = REST_API + "instances/"
+    PORTS_API = REST_API + "ports/"
+    NETWORKS_API = REST_API + "networks/"
+
+    OPENCLOUD_AUTH=(options.username, options.password)
+
+    if options.slice:
+        slice_id = get_slice_id(options.slice)
+    else:
+        slice_id = None
+
+    if options.node:
+        node_id = get_node_id(hostname)
+    else:
+        node_id = None
     instances = get_instances(slice_id, node_id)
 
+    networks = get_networks()
+    networks_by_id = {}
+    for network in networks:
+        networks_by_id[network["id"]] = network
+
     # get (instance_name, ip) pairs for instances with names and ips
 
     instances = [x for x in instances if x["instance_name"]]
     instances = sorted(instances, key = lambda instance: instance["instance_name"])
 
-    # return the last one in the list (i.e. the newest one)
+    for instance in instances:
+        r = requests.get(PORTS_API + "?instance=%s&no_hyperlinks=1" % instance["id"], auth=OPENCLOUD_AUTH)
+        ports = r.json()
 
-    instance_id = instances[-1]["id"]
-
-    r = requests.get(PORTS_API + "?instance=%s" % instance_id, auth=opencloud_auth)
-    ports = r.json()
-    ips = [x["ip"] for x in ports]
-
-    # XXX kinda hackish -- assumes private ips start with "10." and nat start with "172."
-
-    # print a public IP if there is one
-    for ip in ips:
-       if (not ip.startswith("10")) and (not ip.startswith("172")):
-           print ip
-           return
-
-    # otherwise print a privat ip
-    for ip in ips:
-       if (not ip.startswith("172")):
-           print ip
-           return
-
-    # otherwise just print the first one
-    print ips[0]
+        for x in ports:
+           net_name = networks_by_id.get(x["network"],{"name": "unknown"})["name"]
+           if (options.filter_network_name) and (net_name!=options.filter_network_name):
+              continue
+           if options.brief:
+                print x["ip"]
+           else:
+               print instance["instance_name"], net_name, x["ip"]
 
 if __name__ == "__main__":
     main()