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"""
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    Mininet: A simple networking testbed for OpenFlow/SDN!
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author: Bob Lantz (rlantz@cs.stanford.edu)
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author: Brandon Heller (brandonh@stanford.edu)
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Mininet creates scalable OpenFlow test networks by using
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process-based virtualization and network namespaces.
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Simulated hosts are created as processes in separate network
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namespaces. This allows a complete OpenFlow network to be simulated on
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top of a single Linux kernel.
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Each host has:
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A virtual console (pipes to a shell)
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A virtual interfaces (half of a veth pair)
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A parent shell (and possibly some child processes) in a namespace
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Hosts have a network interface which is configured via ifconfig/ip
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link/etc.
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This version supports both the kernel and user space datapaths
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from the OpenFlow reference implementation (openflowswitch.org)
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as well as OpenVSwitch (openvswitch.org.)
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In kernel datapath mode, the controller and switches are simply
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processes in the root namespace.
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Kernel OpenFlow datapaths are instantiated using dpctl(8), and are
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attached to the one side of a veth pair; the other side resides in the
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host namespace. In this mode, switch processes can simply connect to the
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controller via the loopback interface.
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In user datapath mode, the controller and switches can be full-service
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nodes that live in their own network namespaces and have management
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interfaces and IP addresses on a control network (e.g. 192.168.123.1,
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currently routed although it could be bridged.)
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In addition to a management interface, user mode switches also have
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several switch interfaces, halves of veth pairs whose other halves
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reside in the host nodes that the switches are connected to.
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Consistent, straightforward naming is important in order to easily
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identify hosts, switches and controllers, both from the CLI and
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from program code. Interfaces are named to make it easy to identify
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which interfaces belong to which node.
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The basic naming scheme is as follows:
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    Host nodes are named h1-hN
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    Switch nodes are named s1-sN
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    Controller nodes are named c0-cN
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    Interfaces are named {nodename}-eth0 .. {nodename}-ethN
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Note: If the network topology is created using mininet.topo, then
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node numbers are unique among hosts and switches (e.g. we have
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h1..hN and SN..SN+M) and also correspond to their default IP addresses
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of 10.x.y.z/8 where x.y.z is the base-256 representation of N for
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hN. This mapping allows easy determination of a node's IP
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address from its name, e.g. h1 -> 10.0.0.1, h257 -> 10.0.1.1.
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Note also that 10.0.0.1 can often be written as 10.1 for short, e.g.
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"ping 10.1" is equivalent to "ping 10.0.0.1".
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Currently we wrap the entire network in a 'mininet' object, which
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constructs a simulated network based on a network topology created
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using a topology object (e.g. LinearTopo) from mininet.topo or
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mininet.topolib, and a Controller which the switches will connect
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to. Several configuration options are provided for functions such as
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automatically setting MAC addresses, populating the ARP table, or
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even running a set of terminals to allow direct interaction with nodes.
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After the network is created, it can be started using start(), and a
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variety of useful tasks maybe performed, including basic connectivity
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and bandwidth tests and running the mininet CLI.
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Once the network is up and running, test code can easily get access
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to host and switch objects which can then be used for arbitrary
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experiments, typically involving running a series of commands on the
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hosts.
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After all desired tests or activities have been completed, the stop()
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method may be called to shut down the network.
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"""
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import os
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import re
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import select
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import signal
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import random
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from time import sleep
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from itertools import chain, groupby
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from math import ceil
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from mininet.cli import CLI
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from mininet.log import info, error, debug, output, warn
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from mininet.node import Host, OVSKernelSwitch, DefaultController, Controller
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from mininet.nodelib import NAT
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from mininet.link import Link, Intf
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from mininet.util import quietRun, fixLimits, numCores, ensureRoot
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from mininet.util import macColonHex, ipStr, ipParse, netParse, ipAdd
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from mininet.term import cleanUpScreens, makeTerms
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# Mininet version: should be consistent with README and LICENSE
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VERSION = "2.2.0b2"
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class Mininet( object ):
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    "Network emulation with hosts spawned in network namespaces."
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    def __init__( self, topo=None, switch=OVSKernelSwitch, host=Host,
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                  controller=DefaultController, link=Link, intf=Intf,
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                  build=True, xterms=False, cleanup=False, ipBase='10.0.0.0/8',
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                  inNamespace=False,
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                  autoSetMacs=False, autoStaticArp=False, autoPinCpus=False,
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                  listenPort=None, waitConnected=False ):
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        """Create Mininet object.
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           topo: Topo (topology) object or None
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           switch: default Switch class
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           host: default Host class/constructor
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           controller: default Controller class/constructor
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           link: default Link class/constructor
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           intf: default Intf class/constructor
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           ipBase: base IP address for hosts,
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           build: build now from topo?
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           xterms: if build now, spawn xterms?
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           cleanup: if build now, cleanup before creating?
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           inNamespace: spawn switches and controller in net namespaces?
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           autoSetMacs: set MAC addrs automatically like IP addresses?
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           autoStaticArp: set all-pairs static MAC addrs?
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           autoPinCpus: pin hosts to (real) cores (requires CPULimitedHost)?
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           listenPort: base listening port to open; will be incremented for
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               each additional switch in the net if inNamespace=False"""
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        self.topo = topo
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        self.switch = switch
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        self.host = host
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        self.controller = controller
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        self.link = link
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        self.intf = intf
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        self.ipBase = ipBase
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        self.ipBaseNum, self.prefixLen = netParse( self.ipBase )
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        self.nextIP = 1  # start for address allocation
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        self.inNamespace = inNamespace
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        self.xterms = xterms
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        self.cleanup = cleanup
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        self.autoSetMacs = autoSetMacs
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        self.autoStaticArp = autoStaticArp
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        self.autoPinCpus = autoPinCpus
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        self.numCores = numCores()
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        self.nextCore = 0  # next core for pinning hosts to CPUs
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        self.listenPort = listenPort
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        self.waitConn = waitConnected
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        self.hosts = []
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        self.switches = []
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        self.controllers = []
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        self.links = []
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        self.nameToNode = {}  # name to Node (Host/Switch) objects
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        self.terms = []  # list of spawned xterm processes
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        Mininet.init()  # Initialize Mininet if necessary
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        self.built = False
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        if topo and build:
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            self.build()
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    def waitConnected( self, timeout=None, delay=.5 ):
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        """wait for each switch to connect to a controller,
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           up to 5 seconds
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           timeout: time to wait, or None to wait indefinitely
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           delay: seconds to sleep per iteration
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           returns: True if all switches are connected"""
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        info( '*** Waiting for switches to connect\n' )
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        time = 0
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        remaining = list( self.switches )
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        while True:
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            for switch in tuple( remaining ):
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                if switch.connected():
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                    info( '%s ' % switch )
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                    remaining.remove( switch )
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            if not remaining:
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                info( '\n' )
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                return True
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            if time > timeout and timeout is not None:
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                break
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            sleep( delay )
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            time += delay
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        warn( 'Timed out after %d seconds\n' % time )
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        for switch in remaining:
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            if not switch.connected():
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                warn( 'Warning: %s is not connected to a controller\n'
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                      % switch.name )
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            else:
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                remaining.remove( switch )
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        return not remaining
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    def addHost( self, name, cls=None, **params ):
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        """Add host.
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           name: name of host to add
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           cls: custom host class/constructor (optional)
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           params: parameters for host
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           returns: added host"""
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        # Default IP and MAC addresses
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        defaults = { 'ip': ipAdd( self.nextIP,
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                                  ipBaseNum=self.ipBaseNum,
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                                  prefixLen=self.prefixLen ) +
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                                  '/%s' % self.prefixLen }
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        if self.autoSetMacs:
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            defaults[ 'mac' ] = macColonHex( self.nextIP )
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        if self.autoPinCpus:
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            defaults[ 'cores' ] = self.nextCore
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            self.nextCore = ( self.nextCore + 1 ) % self.numCores
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        self.nextIP += 1
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        defaults.update( params )
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        if not cls:
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            cls = self.host
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        h = cls( name, **defaults )
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        self.hosts.append( h )
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        self.nameToNode[ name ] = h
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        return h
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    def addSwitch( self, name, cls=None, **params ):
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        """Add switch.
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           name: name of switch to add
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           cls: custom switch class/constructor (optional)
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           returns: added switch
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           side effect: increments listenPort ivar ."""
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        defaults = { 'listenPort': self.listenPort,
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                     'inNamespace': self.inNamespace }
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        defaults.update( params )
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        if not cls:
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            cls = self.switch
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        sw = cls( name, **defaults )
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        if not self.inNamespace and self.listenPort:
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            self.listenPort += 1
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        self.switches.append( sw )
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        self.nameToNode[ name ] = sw
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        return sw
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    def addController( self, name='c0', controller=None, **params ):
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        """Add controller.
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           controller: Controller class"""
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        # Get controller class
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        if not controller:
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            controller = self.controller
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        # Construct new controller if one is not given
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        if isinstance( name, Controller ):
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            controller_new = name
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            # Pylint thinks controller is a str()
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            # pylint: disable=E1103
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            name = controller_new.name
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            # pylint: enable=E1103
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        else:
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            controller_new = controller( name, **params )
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        # Add new controller to net
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        if controller_new: # allow controller-less setups
263
            self.controllers.append( controller_new )
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            self.nameToNode[ name ] = controller_new
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        return controller_new
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    def addNAT( self, name='nat0', connect=True, inNamespace=False, **params ):
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        nat = self.addHost( name, cls=NAT, inNamespace=inNamespace,
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                            subnet=self.ipBase, **params )
270
        # find first switch and create link
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        if connect:
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            # connect the nat to the first switch
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            self.addLink( nat, self.switches[ 0 ] )
274
            # set the default route on hosts
275
            natIP = nat.params[ 'ip' ].split('/')[ 0 ]
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            for host in self.hosts:
277
                if host.inNamespace:
278
                    host.setDefaultRoute( 'via %s' % natIP )
279
        return nat
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281
    # BL: We now have four ways to look up nodes
282
    # This may (should?) be cleaned up in the future.
283
    def getNodeByName( self, *args ):
284
        "Return node(s) with given name(s)"
285
        if len( args ) == 1:
286
            return self.nameToNode[ args[ 0 ] ]
287
        return [ self.nameToNode[ n ] for n in args ]
288

    
289
    def get( self, *args ):
290
        "Convenience alias for getNodeByName"
291
        return self.getNodeByName( *args )
292

    
293
    # Even more convenient syntax for node lookup and iteration
294
    def __getitem__( self, key ):
295
        """net [ name ] operator: Return node(s) with given name(s)"""
296
        return self.nameToNode[ key ]
297

    
298
    def __iter__( self ):
299
        "return iterator over node names"
300
        for node in chain( self.hosts, self.switches, self.controllers ):
301
            yield node.name
302

    
303
    def __len__( self ):
304
        "returns number of nodes in net"
305
        return ( len( self.hosts ) + len( self.switches ) +
306
                 len( self.controllers ) )
307

    
308
    def __contains__( self, item ):
309
        "returns True if net contains named node"
310
        return item in self.nameToNode
311

    
312
    def keys( self ):
313
        "return a list of all node names or net's keys"
314
        return list( self )
315

    
316
    def values( self ):
317
        "return a list of all nodes or net's values"
318
        return [ self[name] for name in self ]
319

    
320
    def items( self ):
321
        "return (key,value) tuple list for every node in net"
322
        return zip( self.keys(), self.values() )
323

    
324
    @staticmethod
325
    def randMac():
326
        "Return a random, non-multicast MAC address"
327
        return macColonHex( random.randint(1, 2**48 - 1) & 0xfeffffffffff  |
328
                            0x020000000000 )
329

    
330
    def addLink( self, node1, node2, port1=None, port2=None,
331
                 cls=None, **params ):
332
        """"Add a link from node1 to node2
333
            node1: source node (or name)
334
            node2: dest node (or name)
335
            port1: source port (optional)
336
            port2: dest port (optional)
337
            cls: link class (optional)
338
            params: additional link params (optional)
339
            returns: link object"""
340
        # Accept node objects or names
341
        node1 = node1 if not isinstance( node1, basestring ) else self[ node1 ]
342
        node2 = node2 if not isinstance( node2, basestring ) else self[ node2 ]
343
        options = dict( params )
344
        # Port is optional
345
        if port1 is not None:
346
            options.setdefault( 'port1', port1 )
347
        if port2 is not None:
348
            options.setdefault( 'port2', port2 )
349
        # Set default MAC - this should probably be in Link
350
        options.setdefault( 'addr1', self.randMac() )
351
        options.setdefault( 'addr2', self.randMac() )
352
        cls = self.link if cls is None else cls
353
        link = cls( node1, node2, **options )
354
        self.links.append( link )
355
        return link
356

    
357
    def configHosts( self ):
358
        "Configure a set of hosts."
359
        for host in self.hosts:
360
            info( host.name + ' ' )
361
            intf = host.defaultIntf()
362
            if intf:
363
                host.configDefault()
364
            else:
365
                # Don't configure nonexistent intf
366
                host.configDefault( ip=None, mac=None )
367
            # You're low priority, dude!
368
            # BL: do we want to do this here or not?
369
            # May not make sense if we have CPU lmiting...
370
            # quietRun( 'renice +18 -p ' + repr( host.pid ) )
371
            # This may not be the right place to do this, but
372
            # it needs to be done somewhere.
373
        info( '\n' )
374

    
375
    def buildFromTopo( self, topo=None ):
376
        """Build mininet from a topology object
377
           At the end of this function, everything should be connected
378
           and up."""
379

    
380
        # Possibly we should clean up here and/or validate
381
        # the topo
382
        if self.cleanup:
383
            pass
384

    
385
        info( '*** Creating network\n' )
386

    
387
        if not self.controllers and self.controller:
388
            # Add a default controller
389
            info( '*** Adding controller\n' )
390
            classes = self.controller
391
            if not isinstance( classes, list ):
392
                classes = [ classes ]
393
            for i, cls in enumerate( classes ):
394
                # Allow Controller objects because nobody understands currying
395
                if isinstance( cls, Controller ):
396
                    self.addController( cls )
397
                else:
398
                    self.addController( 'c%d' % i, cls )
399

    
400
        info( '*** Adding hosts:\n' )
401
        for hostName in topo.hosts():
402
            self.addHost( hostName, **topo.nodeInfo( hostName ) )
403
            info( hostName + ' ' )
404

    
405
        info( '\n*** Adding switches:\n' )
406
        for switchName in topo.switches():
407
            self.addSwitch( switchName, **topo.nodeInfo( switchName) )
408
            info( switchName + ' ' )
409

    
410
        info( '\n*** Adding links:\n' )
411
        for srcName, dstName, params in topo.links(
412
                sort=True, withInfo=True ):
413
            self.addLink( **params )
414
            info( '(%s, %s) ' % ( srcName, dstName ) )
415

    
416
        info( '\n' )
417

    
418
    def configureControlNetwork( self ):
419
        "Control net config hook: override in subclass"
420
        raise Exception( 'configureControlNetwork: '
421
                         'should be overriden in subclass', self )
422

    
423
    def build( self ):
424
        "Build mininet."
425
        if self.topo:
426
            self.buildFromTopo( self.topo )
427
        if self.inNamespace:
428
            self.configureControlNetwork()
429
        info( '*** Configuring hosts\n' )
430
        self.configHosts()
431
        if self.xterms:
432
            self.startTerms()
433
        if self.autoStaticArp:
434
            self.staticArp()
435
        self.built = True
436

    
437
    def startTerms( self ):
438
        "Start a terminal for each node."
439
        if 'DISPLAY' not in os.environ:
440
            error( "Error starting terms: Cannot connect to display\n" )
441
            return
442
        info( "*** Running terms on %s\n" % os.environ[ 'DISPLAY' ] )
443
        cleanUpScreens()
444
        self.terms += makeTerms( self.controllers, 'controller' )
445
        self.terms += makeTerms( self.switches, 'switch' )
446
        self.terms += makeTerms( self.hosts, 'host' )
447

    
448
    def stopXterms( self ):
449
        "Kill each xterm."
450
        for term in self.terms:
451
            os.kill( term.pid, signal.SIGKILL )
452
        cleanUpScreens()
453

    
454
    def staticArp( self ):
455
        "Add all-pairs ARP entries to remove the need to handle broadcast."
456
        for src in self.hosts:
457
            for dst in self.hosts:
458
                if src != dst:
459
                    src.setARP( ip=dst.IP(), mac=dst.MAC() )
460

    
461
    def start( self ):
462
        "Start controller and switches."
463
        if not self.built:
464
            self.build()
465
        info( '*** Starting controller\n' )
466
        for controller in self.controllers:
467
            info( controller.name + ' ')
468
            controller.start()
469
        info( '\n' )
470
        info( '*** Starting %s switches\n' % len( self.switches ) )
471
        for switch in self.switches:
472
            info( switch.name + ' ')
473
            switch.start( self.controllers )
474
        info( '\n' )
475
        if self.waitConn:
476
            self.waitConnected()
477

    
478
    def stop( self ):
479
        "Stop the controller(s), switches and hosts"
480
        info( '*** Stopping %i controllers\n' % len( self.controllers ) )
481
        for controller in self.controllers:
482
            info( controller.name + ' ' )
483
            controller.stop()
484
        info( '\n' )
485
        if self.terms:
486
            info( '*** Stopping %i terms\n' % len( self.terms ) )
487
            self.stopXterms()
488
        info( '*** Stopping %i switches\n' % len( self.switches ) )
489
        for swclass, switches in groupby( sorted( self.switches, key=type ), type ):
490
            if hasattr( swclass, 'batchShutdown' ):
491
                swclass.batchShutdown( switches )
492
        for switch in self.switches:
493
            info( switch.name + ' ' )
494
            switch.stop()
495
            switch.terminate()
496
        info( '\n' )
497
        info( '*** Stopping %i links\n' % len( self.links ) )
498
        for link in self.links:
499
            link.stop()
500
        info( '\n' )
501
        info( '*** Stopping %i hosts\n' % len( self.hosts ) )
502
        for host in self.hosts:
503
            info( host.name + ' ' )
504
            host.terminate()
505
        info( '\n*** Done\n' )
506

    
507
    def run( self, test, *args, **kwargs ):
508
        "Perform a complete start/test/stop cycle."
509
        self.start()
510
        info( '*** Running test\n' )
511
        result = test( *args, **kwargs )
512
        self.stop()
513
        return result
514

    
515
    def monitor( self, hosts=None, timeoutms=-1 ):
516
        """Monitor a set of hosts (or all hosts by default),
517
           and return their output, a line at a time.
518
           hosts: (optional) set of hosts to monitor
519
           timeoutms: (optional) timeout value in ms
520
           returns: iterator which returns host, line"""
521
        if hosts is None:
522
            hosts = self.hosts
523
        poller = select.poll()
524
        Node = hosts[ 0 ]  # so we can call class method fdToNode
525
        for host in hosts:
526
            poller.register( host.stdout )
527
        while True:
528
            ready = poller.poll( timeoutms )
529
            for fd, event in ready:
530
                host = Node.fdToNode( fd )
531
                if event & select.POLLIN:
532
                    line = host.readline()
533
                    if line is not None:
534
                        yield host, line
535
            # Return if non-blocking
536
            if not ready and timeoutms >= 0:
537
                yield None, None
538

    
539
    # XXX These test methods should be moved out of this class.
540
    # Probably we should create a tests.py for them
541

    
542
    @staticmethod
543
    def _parsePing( pingOutput ):
544
        "Parse ping output and return packets sent, received."
545
        # Check for downed link
546
        if 'connect: Network is unreachable' in pingOutput:
547
            return 1, 0
548
        r = r'(\d+) packets transmitted, (\d+) received'
549
        m = re.search( r, pingOutput )
550
        if m is None:
551
            error( '*** Error: could not parse ping output: %s\n' %
552
                   pingOutput )
553
            return 1, 0
554
        sent, received = int( m.group( 1 ) ), int( m.group( 2 ) )
555
        return sent, received
556

    
557
    def ping( self, hosts=None, timeout=None ):
558
        """Ping between all specified hosts.
559
           hosts: list of hosts
560
           timeout: time to wait for a response, as string
561
           returns: ploss packet loss percentage"""
562
        # should we check if running?
563
        packets = 0
564
        lost = 0
565
        ploss = None
566
        if not hosts:
567
            hosts = self.hosts
568
            output( '*** Ping: testing ping reachability\n' )
569
        for node in hosts:
570
            output( '%s -> ' % node.name )
571
            for dest in hosts:
572
                if node != dest:
573
                    opts = ''
574
                    if timeout:
575
                        opts = '-W %s' % timeout
576
                    if dest.intfs:
577
                        result = node.cmd( 'ping -c1 %s %s' % (opts, dest.IP()) )
578
                        sent, received = self._parsePing( result )
579
                    else:
580
                        sent, received = 0, 0
581
                    packets += sent
582
                    if received > sent:
583
                        error( '*** Error: received too many packets' )
584
                        error( '%s' % result )
585
                        node.cmdPrint( 'route' )
586
                        exit( 1 )
587
                    lost += sent - received
588
                    output( ( '%s ' % dest.name ) if received else 'X ' )
589
            output( '\n' )
590
        if packets > 0:
591
            ploss = 100.0 * lost / packets
592
            received = packets - lost
593
            output( "*** Results: %i%% dropped (%d/%d received)\n" %
594
                    ( ploss, received, packets ) )
595
        else:
596
            ploss = 0
597
            output( "*** Warning: No packets sent\n" )
598
        return ploss
599

    
600
    @staticmethod
601
    def _parsePingFull( pingOutput ):
602
        "Parse ping output and return all data."
603
        errorTuple = (1, 0, 0, 0, 0, 0)
604
        # Check for downed link
605
        r = r'[uU]nreachable'
606
        m = re.search( r, pingOutput )
607
        if m is not None:
608
            return errorTuple
609
        r = r'(\d+) packets transmitted, (\d+) received'
610
        m = re.search( r, pingOutput )
611
        if m is None:
612
            error( '*** Error: could not parse ping output: %s\n' %
613
                   pingOutput )
614
            return errorTuple
615
        sent, received = int( m.group( 1 ) ), int( m.group( 2 ) )
616
        r = r'rtt min/avg/max/mdev = '
617
        r += r'(\d+\.\d+)/(\d+\.\d+)/(\d+\.\d+)/(\d+\.\d+) ms'
618
        m = re.search( r, pingOutput )
619
        if m is None:
620
            if received == 0:
621
                return errorTuple
622
            error( '*** Error: could not parse ping output: %s\n' %
623
                   pingOutput )
624
            return errorTuple
625
        rttmin = float( m.group( 1 ) )
626
        rttavg = float( m.group( 2 ) )
627
        rttmax = float( m.group( 3 ) )
628
        rttdev = float( m.group( 4 ) )
629
        return sent, received, rttmin, rttavg, rttmax, rttdev
630

    
631
    def pingFull( self, hosts=None, timeout=None ):
632
        """Ping between all specified hosts and return all data.
633
           hosts: list of hosts
634
           timeout: time to wait for a response, as string
635
           returns: all ping data; see function body."""
636
        # should we check if running?
637
        # Each value is a tuple: (src, dsd, [all ping outputs])
638
        all_outputs = []
639
        if not hosts:
640
            hosts = self.hosts
641
            output( '*** Ping: testing ping reachability\n' )
642
        for node in hosts:
643
            output( '%s -> ' % node.name )
644
            for dest in hosts:
645
                if node != dest:
646
                    opts = ''
647
                    if timeout:
648
                        opts = '-W %s' % timeout
649
                    result = node.cmd( 'ping -c1 %s %s' % (opts, dest.IP()) )
650
                    outputs = self._parsePingFull( result )
651
                    sent, received, rttmin, rttavg, rttmax, rttdev = outputs
652
                    all_outputs.append( (node, dest, outputs) )
653
                    output( ( '%s ' % dest.name ) if received else 'X ' )
654
            output( '\n' )
655
        output( "*** Results: \n" )
656
        for outputs in all_outputs:
657
            src, dest, ping_outputs = outputs
658
            sent, received, rttmin, rttavg, rttmax, rttdev = ping_outputs
659
            output( " %s->%s: %s/%s, " % (src, dest, sent, received ) )
660
            output( "rtt min/avg/max/mdev %0.3f/%0.3f/%0.3f/%0.3f ms\n" %
661
                    (rttmin, rttavg, rttmax, rttdev) )
662
        return all_outputs
663

    
664
    def pingAll( self, timeout=None ):
665
        """Ping between all hosts.
666
           returns: ploss packet loss percentage"""
667
        return self.ping( timeout=timeout )
668

    
669
    def pingPair( self ):
670
        """Ping between first two hosts, useful for testing.
671
           returns: ploss packet loss percentage"""
672
        hosts = [ self.hosts[ 0 ], self.hosts[ 1 ] ]
673
        return self.ping( hosts=hosts )
674

    
675
    def pingAllFull( self ):
676
        """Ping between all hosts.
677
           returns: ploss packet loss percentage"""
678
        return self.pingFull()
679

    
680
    def pingPairFull( self ):
681
        """Ping between first two hosts, useful for testing.
682
           returns: ploss packet loss percentage"""
683
        hosts = [ self.hosts[ 0 ], self.hosts[ 1 ] ]
684
        return self.pingFull( hosts=hosts )
685

    
686
    @staticmethod
687
    def _parseIperf( iperfOutput ):
688
        """Parse iperf output and return bandwidth.
689
           iperfOutput: string
690
           returns: result string"""
691
        r = r'([\d\.]+ \w+/sec)'
692
        m = re.findall( r, iperfOutput )
693
        if m:
694
            return m[-1]
695
        else:
696
            # was: raise Exception(...)
697
            error( 'could not parse iperf output: ' + iperfOutput )
698
            return ''
699

    
700
    # XXX This should be cleaned up
701

    
702
    def iperf( self, hosts=None, l4Type='TCP', udpBw='10M', format=None,
703
               seconds=5):
704
        """Run iperf between two hosts.
705
           hosts: list of hosts; if None, uses opposite hosts
706
           l4Type: string, one of [ TCP, UDP ]
707
           udpBw: bandwidth target for UDP test
708
           format: iperf format argument if any
709
           seconds: iperf time to transmit
710
           returns: two-element array of [ server, client ] speeds
711
           note: send() is buffered, so client rate can be much higher than
712
           the actual transmission rate; on an unloaded system, server
713
           rate should be much closer to the actual receive rate"""
714
        if not quietRun( 'which telnet' ):
715
            error( 'Cannot find telnet in $PATH - required for iperf test' )
716
            return
717
        if not hosts:
718
            hosts = [ self.hosts[ 0 ], self.hosts[ -1 ] ]
719
        else:
720
            assert len( hosts ) == 2
721
        client, server = hosts
722
        output( '*** Iperf: testing ' + l4Type + ' bandwidth between ' )
723
        output( "%s and %s\n" % ( client.name, server.name ) )
724
        server.cmd( 'killall -9 iperf' )
725
        iperfArgs = 'iperf '
726
        bwArgs = ''
727
        if l4Type == 'UDP':
728
            iperfArgs += '-u '
729
            bwArgs = '-b ' + udpBw + ' '
730
        elif l4Type != 'TCP':
731
            raise Exception( 'Unexpected l4 type: %s' % l4Type )
732
        if format:
733
          iperfArgs += '-f %s ' %format
734
        server.sendCmd( iperfArgs + '-s', printPid=True )
735
        servout = ''
736
        while server.lastPid is None:
737
            servout += server.monitor()
738
        if l4Type == 'TCP':
739
            while 'Connected' not in client.cmd(
740
                    'sh -c "echo A | telnet -e A %s 5001"' % server.IP()):
741
                info( 'Waiting for iperf to start up...' )
742
                sleep(.5)
743
        cliout = client.cmd( iperfArgs + '-t %d -c ' % seconds +
744
                             server.IP() + ' ' + bwArgs )
745
        debug( 'Client output: %s\n' % cliout )
746
        server.sendInt()
747
        servout += server.waitOutput()
748
        debug( 'Server output: %s\n' % servout )
749
        result = [ self._parseIperf( servout ), self._parseIperf( cliout ) ]
750
        if l4Type == 'UDP':
751
            result.insert( 0, udpBw )
752
        output( '*** Results: %s\n' % result )
753
        return result
754

    
755
    def runCpuLimitTest( self, cpu, duration=5 ):
756
        """run CPU limit test with 'while true' processes.
757
        cpu: desired CPU fraction of each host
758
        duration: test duration in seconds
759
        returns a single list of measured CPU fractions as floats.
760
        """
761
        cores = int( quietRun( 'nproc' ) )
762
        pct = cpu * 100
763
        info( '*** Testing CPU %.0f%% bandwidth limit\n' % pct )
764
        hosts = self.hosts
765
        cores = int( quietRun( 'nproc' ) )
766
        # number of processes to run a while loop on per host
767
        num_procs = int( ceil( cores * cpu ) )
768
        pids = {}
769
        for h in hosts:
770
            pids[ h ] = []
771
            for _core in range( num_procs ):
772
                h.cmd( 'while true; do a=1; done &' )
773
                pids[ h ].append( h.cmd( 'echo $!' ).strip() )
774
        outputs = {}
775
        time = {}
776
        # get the initial cpu time for each host
777
        for host in hosts:
778
            outputs[ host ] = []
779
            with open( '/sys/fs/cgroup/cpuacct/%s/cpuacct.usage' % host, 'r' ) as f:
780
                time[ host ] = float( f.read() )
781
        for _ in range( 5 ):
782
            sleep( 1 )
783
            for host in hosts:
784
                with open( '/sys/fs/cgroup/cpuacct/%s/cpuacct.usage' % host, 'r' ) as f:
785
                    readTime = float( f.read() )
786
                outputs[ host ].append( ( ( readTime - time[ host ] )
787
                                        / 1000000000 ) / cores * 100 )
788
                time[ host ] = readTime
789
        for h, pids in pids.items():
790
            for pid in pids:
791
                h.cmd( 'kill -9 %s' % pid )
792
        cpu_fractions = []
793
        for _host, outputs in outputs.items():
794
            for pct in outputs:
795
                cpu_fractions.append( pct )
796
        output( '*** Results: %s\n' % cpu_fractions )
797
        return cpu_fractions
798

    
799
    # BL: I think this can be rewritten now that we have
800
    # a real link class.
801
    def configLinkStatus( self, src, dst, status ):
802
        """Change status of src <-> dst links.
803
           src: node name
804
           dst: node name
805
           status: string {up, down}"""
806
        if src not in self.nameToNode:
807
            error( 'src not in network: %s\n' % src )
808
        elif dst not in self.nameToNode:
809
            error( 'dst not in network: %s\n' % dst )
810
        else:
811
            if isinstance( src, basestring ):
812
                src = self.nameToNode[ src ]
813
            if isinstance( dst, basestring ):
814
                dst = self.nameToNode[ dst ]
815
            connections = src.connectionsTo( dst )
816
            if len( connections ) == 0:
817
                error( 'src and dst not connected: %s %s\n' % ( src, dst) )
818
            for srcIntf, dstIntf in connections:
819
                result = srcIntf.ifconfig( status )
820
                if result:
821
                    error( 'link src status change failed: %s\n' % result )
822
                result = dstIntf.ifconfig( status )
823
                if result:
824
                    error( 'link dst status change failed: %s\n' % result )
825

    
826
    def interact( self ):
827
        "Start network and run our simple CLI."
828
        self.start()
829
        result = CLI( self )
830
        self.stop()
831
        return result
832

    
833
    inited = False
834

    
835
    @classmethod
836
    def init( cls ):
837
        "Initialize Mininet"
838
        if cls.inited:
839
            return
840
        ensureRoot()
841
        fixLimits()
842
        cls.inited = True
843

    
844

    
845
class MininetWithControlNet( Mininet ):
846

    
847
    """Control network support:
848

849
       Create an explicit control network. Currently this is only
850
       used/usable with the user datapath.
851

852
       Notes:
853

854
       1. If the controller and switches are in the same (e.g. root)
855
          namespace, they can just use the loopback connection.
856

857
       2. If we can get unix domain sockets to work, we can use them
858
          instead of an explicit control network.
859

860
       3. Instead of routing, we could bridge or use 'in-band' control.
861

862
       4. Even if we dispense with this in general, it could still be
863
          useful for people who wish to simulate a separate control
864
          network (since real networks may need one!)
865

866
       5. Basically nobody ever used this code, so it has been moved
867
          into its own class.
868

869
       6. Ultimately we may wish to extend this to allow us to create a
870
          control network which every node's control interface is
871
          attached to."""
872

    
873
    def configureControlNetwork( self ):
874
        "Configure control network."
875
        self.configureRoutedControlNetwork()
876

    
877
    # We still need to figure out the right way to pass
878
    # in the control network location.
879

    
880
    def configureRoutedControlNetwork( self, ip='192.168.123.1',
881
                                       prefixLen=16 ):
882
        """Configure a routed control network on controller and switches.
883
           For use with the user datapath only right now."""
884
        controller = self.controllers[ 0 ]
885
        info( controller.name + ' <->' )
886
        cip = ip
887
        snum = ipParse( ip )
888
        for switch in self.switches:
889
            info( ' ' + switch.name )
890
            link = self.link( switch, controller, port1=0 )
891
            sintf, cintf = link.intf1, link.intf2
892
            switch.controlIntf = sintf
893
            snum += 1
894
            while snum & 0xff in [ 0, 255 ]:
895
                snum += 1
896
            sip = ipStr( snum )
897
            cintf.setIP( cip, prefixLen )
898
            sintf.setIP( sip, prefixLen )
899
            controller.setHostRoute( sip, cintf )
900
            switch.setHostRoute( cip, sintf )
901
        info( '\n' )
902
        info( '*** Testing control network\n' )
903
        while not cintf.isUp():
904
            info( '*** Waiting for', cintf, 'to come up\n' )
905
            sleep( 1 )
906
        for switch in self.switches:
907
            while not sintf.isUp():
908
                info( '*** Waiting for', sintf, 'to come up\n' )
909
                sleep( 1 )
910
            if self.ping( hosts=[ switch, controller ] ) != 0:
911
                error( '*** Error: control network test failed\n' )
912
                exit( 1 )
913
        info( '\n' )