Python utility that attempts to listen on a wide range of ports. Designed to help test the OS open files limit.

stress_sockets.py

#!/usr/bin/env python
"""
Python utility that attempts to listen on a wide range of ports.

Designed to stress test the OS open files limit.
"""
import argparse
import socket

parser = argparse.ArgumentParser(
    "Listen on a range of ports. Does not actually accept connections.",
    formatter_class=argparse.ArgumentDefaultsHelpFormatter)
parser.add_argument("-p", "--start_port", type=int, help="starting port", default=1042)
parser.add_argument("-n", "--num_ports", type=int, help="number of ports to attempt to listen to", default=5000)
parser.add_argument("--host", type=str, help="host", default="")
parser.add_argument("-d", "--debug", action='store_true', help="whether to enable debugging", default=False)
parser.add_argument("-b", "--backlog", type=int, help="socket backlog", default=5)

ARGS = parser.parse_args()

SOCKETS = []

def main():
    errors = []
    for port in xrange(ARGS.start_port, ARGS.start_port + ARGS.num_ports):
        try:
            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            s.bind((ARGS.host, port))
            s.listen(ARGS.backlog)
            SOCKETS.append(s)
            if ARGS.debug:
                print "Listening on port %s" % port
        except Exception, e:
            errors.append(e)
            if ARGS.debug:
                print "Error while listening on port %s: %s" % (port, e)

    print "# of sockets: %d" % len(SOCKETS)
    print "# of errors: %d" % len(errors)

if __name__ == '__main__':
    main()