'Start up a new IVS switch'

def start(self, controllers):

    args = ['ivs']
    args.extend(['--name', self.name])
    args.extend(['--dpid', self.dpid])
    if self.verbose:
        args.extend(['--verbose'])
    for intf in self.intfs.values():
        if (not intf.IP()):
            args.extend(['-i', intf.name])
    for c in controllers:
        args.extend(['-c', ('%s:%d' % (c.IP(), c.port))])
    if self.listenPort:
        args.extend(['--listen', ('127.0.0.1:%i' % self.listenPort)])
    args.append(self.opts)
    logfile = ('/tmp/ivs.%s.log' % self.name)
    self.cmd(((('    '.join(args) + '    >') + logfile) + '    2>&1    </dev/null    &'))
