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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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from time import sleep
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from itertools import chain
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from mininet.cli import CLI
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from mininet.log import info, error, debug, output
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from mininet.node import Host, OVSKernelSwitch, Controller
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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 = "2.1.0+"
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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=Controller, 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 ):
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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.hosts = []
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        self.switches = []
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        self.controllers = []
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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 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
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            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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    # BL: We now have four ways to look up nodes
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    # This may (should?) be cleaned up in the future.
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    def getNodeByName( self, *args ):
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        "Return node(s) with given name(s)"
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        if len( args ) == 1:
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            return self.nameToNode[ args[ 0 ] ]
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        return [ self.nameToNode[ n ] for n in args ]
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    def get( self, *args ):
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        "Convenience alias for getNodeByName"
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        return self.getNodeByName( *args )
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    # Even more convenient syntax for node lookup and iteration
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    def __getitem__( self, key ):
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        """net [ name ] operator: Return node(s) with given name(s)"""
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        return self.nameToNode[ key ]
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    def __iter__( self ):
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        "return iterator over node names"
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        for node in chain( self.hosts, self.switches, self.controllers ):
250
            yield node.name
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    def __len__( self ):
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        "returns number of nodes in net"
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        return ( len( self.hosts ) + len( self.switches ) +
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                 len( self.controllers ) )
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    def __contains__( self, item ):
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        "returns True if net contains named node"
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        return item in self.nameToNode
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    def keys( self ):
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        "return a list of all node names or net's keys"
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        return list( self )
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    def values( self ):
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        "return a list of all nodes or net's values"
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        return [ self[name] for name in self ]
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    def items( self ):
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        "return (key,value) tuple list for every node in net"
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        return zip( self.keys(), self.values() )
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    def addLink( self, node1, node2, port1=None, port2=None,
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                 cls=None, **params ):
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        """"Add a link from node1 to node2
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            node1: source node
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            node2: dest node
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            port1: source port
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            port2: dest port
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            returns: link object"""
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        defaults = { 'port1': port1,
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                     'port2': port2,
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                     'intf': self.intf }
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        defaults.update( params )
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        if not cls:
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            cls = self.link
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        return cls( node1, node2, **defaults )
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289
    def configHosts( self ):
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        "Configure a set of hosts."
291
        for host in self.hosts:
292
            info( host.name + ' ' )
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            intf = host.defaultIntf()
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            if intf:
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                host.configDefault()
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            else:
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                # Don't configure nonexistent intf
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                host.configDefault( ip=None, mac=None )
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            # You're low priority, dude!
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            # BL: do we want to do this here or not?
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            # May not make sense if we have CPU lmiting...
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            # quietRun( 'renice +18 -p ' + repr( host.pid ) )
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            # This may not be the right place to do this, but
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            # it needs to be done somewhere.
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            host.cmd( 'ifconfig lo up' )
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        info( '\n' )
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    def buildFromTopo( self, topo=None ):
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        """Build mininet from a topology object
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           At the end of this function, everything should be connected
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           and up."""
312

    
313
        # Possibly we should clean up here and/or validate
314
        # the topo
315
        if self.cleanup:
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            pass
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318
        info( '*** Creating network\n' )
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320
        if not self.controllers and self.controller:
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            # Add a default controller
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            info( '*** Adding controller\n' )
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            classes = self.controller
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            if type( classes ) is not list:
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                classes = [ classes ]
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            for i, cls in enumerate( classes ):
327
                self.addController( 'c%d' % i, cls )
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329
        info( '*** Adding hosts:\n' )
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        for hostName in topo.hosts():
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            self.addHost( hostName, **topo.nodeInfo( hostName ) )
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            info( hostName + ' ' )
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334
        info( '\n*** Adding switches:\n' )
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        for switchName in topo.switches():
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            self.addSwitch( switchName, **topo.nodeInfo( switchName) )
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            info( switchName + ' ' )
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339
        info( '\n*** Adding links:\n' )
340
        for srcName, dstName in topo.links(sort=True):
341
            src, dst = self.nameToNode[ srcName ], self.nameToNode[ dstName ]
342
            params = topo.linkInfo( srcName, dstName )
343
            srcPort, dstPort = topo.port( srcName, dstName )
344
            self.addLink( src, dst, srcPort, dstPort, **params )
345
            info( '(%s, %s) ' % ( src.name, dst.name ) )
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347
        info( '\n' )
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349
    def configureControlNetwork( self ):
350
        "Control net config hook: override in subclass"
351
        raise Exception( 'configureControlNetwork: '
352
                         'should be overriden in subclass', self )
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354
    def build( self ):
355
        "Build mininet."
356
        if self.topo:
357
            self.buildFromTopo( self.topo )
358
        if self.inNamespace:
359
            self.configureControlNetwork()
360
        info( '*** Configuring hosts\n' )
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        self.configHosts()
362
        if self.xterms:
363
            self.startTerms()
364
        if self.autoStaticArp:
365
            self.staticArp()
366
        self.built = True
367

    
368
    def startTerms( self ):
369
        "Start a terminal for each node."
370
        if 'DISPLAY' not in os.environ:
371
            error( "Error starting terms: Cannot connect to display\n" )
372
            return
373
        info( "*** Running terms on %s\n" % os.environ[ 'DISPLAY' ] )
374
        cleanUpScreens()
375
        self.terms += makeTerms( self.controllers, 'controller' )
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        self.terms += makeTerms( self.switches, 'switch' )
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        self.terms += makeTerms( self.hosts, 'host' )
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379
    def stopXterms( self ):
380
        "Kill each xterm."
381
        for term in self.terms:
382
            os.kill( term.pid, signal.SIGKILL )
383
        cleanUpScreens()
384

    
385
    def staticArp( self ):
386
        "Add all-pairs ARP entries to remove the need to handle broadcast."
387
        for src in self.hosts:
388
            for dst in self.hosts:
389
                if src != dst:
390
                    src.setARP( ip=dst.IP(), mac=dst.MAC() )
391

    
392
    def start( self ):
393
        "Start controller and switches."
394
        if not self.built:
395
            self.build()
396
        info( '*** Starting controller\n' )
397
        for controller in self.controllers:
398
            controller.start()
399
        info( '*** Starting %s switches\n' % len( self.switches ) )
400
        for switch in self.switches:
401
            info( switch.name + ' ')
402
            switch.start( self.controllers )
403
        info( '\n' )
404

    
405
    def stop( self ):
406
        "Stop the controller(s), switches and hosts"
407
        if self.terms:
408
            info( '*** Stopping %i terms\n' % len( self.terms ) )
409
            self.stopXterms()
410
        info( '*** Stopping %i switches\n' % len( self.switches ) )
411
        if self.switches:
412
            swclass = type( self.switches[ 0 ] )
413
            if hasattr( swclass, 'batchShutdown' ):
414
                swclass.batchShutdown( self.switches )
415
        for switch in self.switches:
416
            info( switch.name + ' ' )
417
            switch.stop()
418
        info( '\n' )
419
        info( '*** Stopping %i hosts\n' % len( self.hosts ) )
420
        for host in self.hosts:
421
            info( host.name + ' ' )
422
            host.terminate()
423
        info( '\n' )
424
        info( '*** Stopping %i controllers\n' % len( self.controllers ) )
425
        for controller in self.controllers:
426
            info( controller.name + ' ' )
427
            controller.stop()
428
        info( '\n*** Done\n' )
429

    
430
    def run( self, test, *args, **kwargs ):
431
        "Perform a complete start/test/stop cycle."
432
        self.start()
433
        info( '*** Running test\n' )
434
        result = test( *args, **kwargs )
435
        self.stop()
436
        return result
437

    
438
    def monitor( self, hosts=None, timeoutms=-1 ):
439
        """Monitor a set of hosts (or all hosts by default),
440
           and return their output, a line at a time.
441
           hosts: (optional) set of hosts to monitor
442
           timeoutms: (optional) timeout value in ms
443
           returns: iterator which returns host, line"""
444
        if hosts is None:
445
            hosts = self.hosts
446
        poller = select.poll()
447
        Node = hosts[ 0 ]  # so we can call class method fdToNode
448
        for host in hosts:
449
            poller.register( host.stdout )
450
        while True:
451
            ready = poller.poll( timeoutms )
452
            for fd, event in ready:
453
                host = Node.fdToNode( fd )
454
                if event & select.POLLIN:
455
                    line = host.readline()
456
                    if line is not None:
457
                        yield host, line
458
            # Return if non-blocking
459
            if not ready and timeoutms >= 0:
460
                yield None, None
461

    
462
    # XXX These test methods should be moved out of this class.
463
    # Probably we should create a tests.py for them
464

    
465
    @staticmethod
466
    def _parsePing( pingOutput ):
467
        "Parse ping output and return packets sent, received."
468
        # Check for downed link
469
        if 'connect: Network is unreachable' in pingOutput:
470
            return 1, 0
471
        r = r'(\d+) packets transmitted, (\d+) received'
472
        m = re.search( r, pingOutput )
473
        if m is None:
474
            error( '*** Error: could not parse ping output: %s\n' %
475
                   pingOutput )
476
            return 1, 0
477
        sent, received = int( m.group( 1 ) ), int( m.group( 2 ) )
478
        return sent, received
479

    
480
    def ping( self, hosts=None, timeout=None ):
481
        """Ping between all specified hosts.
482
           hosts: list of hosts
483
           timeout: time to wait for a response, as string
484
           returns: ploss packet loss percentage"""
485
        # should we check if running?
486
        packets = 0
487
        lost = 0
488
        ploss = None
489
        if not hosts:
490
            hosts = self.hosts
491
            output( '*** Ping: testing ping reachability\n' )
492
        for node in hosts:
493
            output( '%s -> ' % node.name )
494
            for dest in hosts:
495
                if node != dest:
496
                    opts = ''
497
                    if timeout:
498
                        opts = '-W %s' % timeout
499
                    result = node.cmd( 'ping -c1 %s %s' % (opts, dest.IP()) )
500
                    sent, received = self._parsePing( result )
501
                    packets += sent
502
                    if received > sent:
503
                        error( '*** Error: received too many packets' )
504
                        error( '%s' % result )
505
                        node.cmdPrint( 'route' )
506
                        exit( 1 )
507
                    lost += sent - received
508
                    output( ( '%s ' % dest.name ) if received else 'X ' )
509
            output( '\n' )
510
        if packets > 0:
511
            ploss = 100.0 * lost / packets
512
            received = packets - lost
513
            output( "*** Results: %i%% dropped (%d/%d received)\n" %
514
                    ( ploss, received, packets ) )
515
        else:
516
            ploss = 0
517
            output( "*** Warning: No packets sent\n" )
518
        return ploss
519

    
520
    @staticmethod
521
    def _parsePingFull( pingOutput ):
522
        "Parse ping output and return all data."
523
        errorTuple = (1, 0, 0, 0, 0, 0)
524
        # Check for downed link
525
        r = r'[uU]nreachable'
526
        m = re.search( r, pingOutput )
527
        if m is not None:
528
            return errorTuple
529
        r = r'(\d+) packets transmitted, (\d+) received'
530
        m = re.search( r, pingOutput )
531
        if m is None:
532
            error( '*** Error: could not parse ping output: %s\n' %
533
                   pingOutput )
534
            return errorTuple
535
        sent, received = int( m.group( 1 ) ), int( m.group( 2 ) )
536
        r = r'rtt min/avg/max/mdev = '
537
        r += r'(\d+\.\d+)/(\d+\.\d+)/(\d+\.\d+)/(\d+\.\d+) ms'
538
        m = re.search( r, pingOutput )
539
        if m is None:
540
            error( '*** Error: could not parse ping output: %s\n' %
541
                   pingOutput )
542
            return errorTuple
543
        rttmin = float( m.group( 1 ) )
544
        rttavg = float( m.group( 2 ) )
545
        rttmax = float( m.group( 3 ) )
546
        rttdev = float( m.group( 4 ) )
547
        return sent, received, rttmin, rttavg, rttmax, rttdev
548

    
549
    def pingFull( self, hosts=None, timeout=None ):
550
        """Ping between all specified hosts and return all data.
551
           hosts: list of hosts
552
           timeout: time to wait for a response, as string
553
           returns: all ping data; see function body."""
554
        # should we check if running?
555
        # Each value is a tuple: (src, dsd, [all ping outputs])
556
        all_outputs = []
557
        if not hosts:
558
            hosts = self.hosts
559
            output( '*** Ping: testing ping reachability\n' )
560
        for node in hosts:
561
            output( '%s -> ' % node.name )
562
            for dest in hosts:
563
                if node != dest:
564
                    opts = ''
565
                    if timeout:
566
                        opts = '-W %s' % timeout
567
                    result = node.cmd( 'ping -c1 %s %s' % (opts, dest.IP()) )
568
                    outputs = self._parsePingFull( result )
569
                    sent, received, rttmin, rttavg, rttmax, rttdev = outputs
570
                    all_outputs.append( (node, dest, outputs) )
571
                    output( ( '%s ' % dest.name ) if received else 'X ' )
572
            output( '\n' )
573
        output( "*** Results: \n" )
574
        for outputs in all_outputs:
575
            src, dest, ping_outputs = outputs
576
            sent, received, rttmin, rttavg, rttmax, rttdev = ping_outputs
577
            output( " %s->%s: %s/%s, " % (src, dest, sent, received ) )
578
            output( "rtt min/avg/max/mdev %0.3f/%0.3f/%0.3f/%0.3f ms\n" %
579
                    (rttmin, rttavg, rttmax, rttdev) )
580
        return all_outputs
581

    
582
    def pingAll( self, timeout=None ):
583
        """Ping between all hosts.
584
           returns: ploss packet loss percentage"""
585
        return self.ping( timeout=timeout )
586

    
587
    def pingPair( self ):
588
        """Ping between first two hosts, useful for testing.
589
           returns: ploss packet loss percentage"""
590
        hosts = [ self.hosts[ 0 ], self.hosts[ 1 ] ]
591
        return self.ping( hosts=hosts )
592

    
593
    def pingAllFull( self ):
594
        """Ping between all hosts.
595
           returns: ploss packet loss percentage"""
596
        return self.pingFull()
597

    
598
    def pingPairFull( self ):
599
        """Ping between first two hosts, useful for testing.
600
           returns: ploss packet loss percentage"""
601
        hosts = [ self.hosts[ 0 ], self.hosts[ 1 ] ]
602
        return self.pingFull( hosts=hosts )
603

    
604
    @staticmethod
605
    def _parseIperf( iperfOutput ):
606
        """Parse iperf output and return bandwidth.
607
           iperfOutput: string
608
           returns: result string"""
609
        r = r'([\d\.]+ \w+/sec)'
610
        m = re.findall( r, iperfOutput )
611
        if m:
612
            return m[-1]
613
        else:
614
            # was: raise Exception(...)
615
            error( 'could not parse iperf output: ' + iperfOutput )
616
            return ''
617

    
618
    # XXX This should be cleaned up
619

    
620
    def iperf( self, hosts=None, l4Type='TCP', udpBw='10M', format='M' ):
621
        """Run iperf between two hosts.
622
           hosts: list of hosts; if None, uses opposite hosts
623
           l4Type: string, one of [ TCP, UDP ]
624
           returns: results two-element array of server and client speeds"""
625
        if not quietRun( 'which telnet' ):
626
            error( 'Cannot find telnet in $PATH - required for iperf test' )
627
            return
628
        if not hosts:
629
            hosts = [ self.hosts[ 0 ], self.hosts[ -1 ] ]
630
        else:
631
            assert len( hosts ) == 2
632
        client, server = hosts
633
        output( '*** Iperf: testing ' + l4Type + ' bandwidth between ' )
634
        output( "%s and %s\n" % ( client.name, server.name ) )
635
        server.cmd( 'killall -9 iperf' )
636
        iperfArgs = 'iperf '
637
        bwArgs = ''
638
        if l4Type == 'UDP':
639
            iperfArgs += '-u '
640
            bwArgs = '-b ' + udpBw + ' '
641
        elif l4Type != 'TCP':
642
            raise Exception( 'Unexpected l4 type: %s' % l4Type )
643
        if not format == 'M':
644
          iperfArgs += '-f %s ' %format
645
        server.sendCmd( iperfArgs + '-s', printPid=True )
646
        servout = ''
647
        while server.lastPid is None:
648
            servout += server.monitor()
649
        if l4Type == 'TCP':
650
            while 'Connected' not in client.cmd(
651
                    'sh -c "echo A | telnet -e A %s 5001"' % server.IP()):
652
                output('waiting for iperf to start up...')
653
                sleep(.5)
654
        cliout = client.cmd( iperfArgs + '-t 5 -c ' + server.IP() + ' ' +
655
                             bwArgs )
656
        debug( 'Client output: %s\n' % cliout )
657
        server.sendInt()
658
        servout += server.waitOutput()
659
        debug( 'Server output: %s\n' % servout )
660
        result = [ self._parseIperf( servout ), self._parseIperf( cliout ) ]
661
        if l4Type == 'UDP':
662
            result.insert( 0, udpBw )
663
        output( '*** Results: %s\n' % result )
664
        return result
665

    
666
    def runCpuLimitTest( self, cpu, duration=5 ):
667
        """run CPU limit test with 'while true' processes.
668
        cpu: desired CPU fraction of each host
669
        duration: test duration in seconds
670
        returns a single list of measured CPU fractions as floats.
671
        """
672
        pct = cpu * 100
673
        info('*** Testing CPU %.0f%% bandwidth limit\n' % pct)
674
        hosts = self.hosts
675
        for h in hosts:
676
            h.cmd( 'while true; do a=1; done &' )
677
        pids = [h.cmd( 'echo $!' ).strip() for h in hosts]
678
        pids_str = ",".join(["%s" % pid for pid in pids])
679
        cmd = 'ps -p %s -o pid,%%cpu,args' % pids_str
680
        # It's a shame that this is what pylint prefers
681
        outputs = []
682
        for _ in range( duration ):
683
            sleep( 1 )
684
            outputs.append( quietRun( cmd ).strip() )
685
        for h in hosts:
686
            h.cmd( 'kill %1' )
687
        cpu_fractions = []
688
        for test_output in outputs:
689
            # Split by line.  Ignore first line, which looks like this:
690
            # PID %CPU COMMAND\n
691
            for line in test_output.split('\n')[1:]:
692
                r = r'\d+\s*(\d+\.\d+)'
693
                m = re.search( r, line )
694
                if m is None:
695
                    error( '*** Error: could not extract CPU fraction: %s\n' %
696
                           line )
697
                    return None
698
                cpu_fractions.append( float( m.group( 1 ) ) )
699
        output( '*** Results: %s\n' % cpu_fractions )
700
        return cpu_fractions
701

    
702
    # BL: I think this can be rewritten now that we have
703
    # a real link class.
704
    def configLinkStatus( self, src, dst, status ):
705
        """Change status of src <-> dst links.
706
           src: node name
707
           dst: node name
708
           status: string {up, down}"""
709
        if src not in self.nameToNode:
710
            error( 'src not in network: %s\n' % src )
711
        elif dst not in self.nameToNode:
712
            error( 'dst not in network: %s\n' % dst )
713
        else:
714
            if type( src ) is str:
715
                src = self.nameToNode[ src ]
716
            if type( dst ) is str:
717
                dst = self.nameToNode[ dst ]
718
            connections = src.connectionsTo( dst )
719
            if len( connections ) == 0:
720
                error( 'src and dst not connected: %s %s\n' % ( src, dst) )
721
            for srcIntf, dstIntf in connections:
722
                result = srcIntf.ifconfig( status )
723
                if result:
724
                    error( 'link src status change failed: %s\n' % result )
725
                result = dstIntf.ifconfig( status )
726
                if result:
727
                    error( 'link dst status change failed: %s\n' % result )
728

    
729
    def interact( self ):
730
        "Start network and run our simple CLI."
731
        self.start()
732
        result = CLI( self )
733
        self.stop()
734
        return result
735

    
736
    inited = False
737

    
738
    @classmethod
739
    def init( cls ):
740
        "Initialize Mininet"
741
        if cls.inited:
742
            return
743
        ensureRoot()
744
        fixLimits()
745
        cls.inited = True
746

    
747

    
748
class MininetWithControlNet( Mininet ):
749

    
750
    """Control network support:
751

752
       Create an explicit control network. Currently this is only
753
       used/usable with the user datapath.
754

755
       Notes:
756

757
       1. If the controller and switches are in the same (e.g. root)
758
          namespace, they can just use the loopback connection.
759

760
       2. If we can get unix domain sockets to work, we can use them
761
          instead of an explicit control network.
762

763
       3. Instead of routing, we could bridge or use 'in-band' control.
764

765
       4. Even if we dispense with this in general, it could still be
766
          useful for people who wish to simulate a separate control
767
          network (since real networks may need one!)
768

769
       5. Basically nobody ever used this code, so it has been moved
770
          into its own class.
771

772
       6. Ultimately we may wish to extend this to allow us to create a
773
          control network which every node's control interface is
774
          attached to."""
775

    
776
    def configureControlNetwork( self ):
777
        "Configure control network."
778
        self.configureRoutedControlNetwork()
779

    
780
    # We still need to figure out the right way to pass
781
    # in the control network location.
782

    
783
    def configureRoutedControlNetwork( self, ip='192.168.123.1',
784
                                       prefixLen=16 ):
785
        """Configure a routed control network on controller and switches.
786
           For use with the user datapath only right now."""
787
        controller = self.controllers[ 0 ]
788
        info( controller.name + ' <->' )
789
        cip = ip
790
        snum = ipParse( ip )
791
        for switch in self.switches:
792
            info( ' ' + switch.name )
793
            link = self.link( switch, controller, port1=0 )
794
            sintf, cintf = link.intf1, link.intf2
795
            switch.controlIntf = sintf
796
            snum += 1
797
            while snum & 0xff in [ 0, 255 ]:
798
                snum += 1
799
            sip = ipStr( snum )
800
            cintf.setIP( cip, prefixLen )
801
            sintf.setIP( sip, prefixLen )
802
            controller.setHostRoute( sip, cintf )
803
            switch.setHostRoute( cip, sintf )
804
        info( '\n' )
805
        info( '*** Testing control network\n' )
806
        while not cintf.isUp():
807
            info( '*** Waiting for', cintf, 'to come up\n' )
808
            sleep( 1 )
809
        for switch in self.switches:
810
            while not sintf.isUp():
811
                info( '*** Waiting for', sintf, 'to come up\n' )
812
                sleep( 1 )
813
            if self.ping( hosts=[ switch, controller ] ) != 0:
814
                error( '*** Error: control network test failed\n' )
815
                exit( 1 )
816
        info( '\n' )