diff --git a/aws-experiment-launch/collect_public_ips.py b/aws-experiment-launch/collect_public_ips.py
index 63f520ee1..c0f40e494 100644
--- a/aws-experiment-launch/collect_public_ips.py
+++ b/aws-experiment-launch/collect_public_ips.py
@@ -1,22 +1,30 @@
 import argparse
+import os
 import sys
 
 from utils import utils
 
 if __name__ == "__main__":
     parser = argparse.ArgumentParser(description='This script helps you to collect public ips')
-    parser.add_argument('--region', type=str, dest='region_number',
-                        default="4", help="region number")
-    parser.add_argument('--node_name_tag', type=str,
-                        dest='node_name_tag', default='4-NODE-23-36-01-2018-07-05')
+    parser.add_argument('--instance_output', type=str, dest='instance_output',
+                        default='instance_output.txt',
+                        help='the file contains node_name_tag and region number of created instances.')
     parser.add_argument('--region_config', type=str,
                         dest='region_config', default='configuration.txt')
     parser.add_argument('--file_output', type=str,
                         dest='file_output', default='raw_ip.txt')
     args = parser.parse_args()
 
-    ip_list = utils.collect_public_ips(args.region_number, args.node_name_tag, args.region_config)
-    with open(args.file_output, "w") as fout:
-        for ip in ip_list:
-            fout.write(ip + " " + args.node_name_tag + "\n")
-    print "Done writing %s" % args.file_output
+    if not args.instance_output or not args.instance_output or not os.path.isfile(args.instance_output):
+        print "%s or %s are not existed" % (args.file_output, args.instance_output)
+        sys.exit(1)
+    if args.instance_output:
+        with open(args.instance_output, "r") as fin, open(args.file_output, "w") as fout:
+            for line in fin.readlines():
+                items = line.split(" ")
+                region_number = items[1].strip()
+                node_name_tag = items[0].strip()
+                ip_list = utils.collect_public_ips(region_number, node_name_tag, args.region_config)
+                for ip in ip_list:
+                    fout.write(ip + " " + node_name_tag + "\n")
+        print "Done collecting public ips %s" % args.file_output