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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, groupby
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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, DefaultController, 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=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 ):
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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 ):
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            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 ):
275
        """"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 )
285
        if not cls:
286
            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."
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        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

    
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        # Possibly we should clean up here and/or validate
314
        # the topo
315
        if self.cleanup:
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            pass
317

    
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 ):
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                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' )
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        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 )
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            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' )
361
        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."
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        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' )
377
        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
        for swclass, switches in groupby( sorted( self.switches, key=type ), type ):
412
            if hasattr( swclass, 'batchShutdown' ):
413
                swclass.batchShutdown( switches )
414
        for switch in self.switches:
415
            info( switch.name + ' ' )
416
            switch.stop()
417
        info( '\n' )
418
        info( '*** Stopping %i hosts\n' % len( self.hosts ) )
419
        for host in self.hosts:
420
            info( host.name + ' ' )
421
            host.terminate()
422
        info( '\n' )
423
        info( '*** Stopping %i controllers\n' % len( self.controllers ) )
424
        for controller in self.controllers:
425
            info( controller.name + ' ' )
426
            controller.stop()
427
        info( '\n*** Done\n' )
428

    
429
    def run( self, test, *args, **kwargs ):
430
        "Perform a complete start/test/stop cycle."
431
        self.start()
432
        info( '*** Running test\n' )
433
        result = test( *args, **kwargs )
434
        self.stop()
435
        return result
436

    
437
    def monitor( self, hosts=None, timeoutms=-1 ):
438
        """Monitor a set of hosts (or all hosts by default),
439
           and return their output, a line at a time.
440
           hosts: (optional) set of hosts to monitor
441
           timeoutms: (optional) timeout value in ms
442
           returns: iterator which returns host, line"""
443
        if hosts is None:
444
            hosts = self.hosts
445
        poller = select.poll()
446
        Node = hosts[ 0 ]  # so we can call class method fdToNode
447
        for host in hosts:
448
            poller.register( host.stdout )
449
        while True:
450
            ready = poller.poll( timeoutms )
451
            for fd, event in ready:
452
                host = Node.fdToNode( fd )
453
                if event & select.POLLIN:
454
                    line = host.readline()
455
                    if line is not None:
456
                        yield host, line
457
            # Return if non-blocking
458
            if not ready and timeoutms >= 0:
459
                yield None, None
460

    
461
    # XXX These test methods should be moved out of this class.
462
    # Probably we should create a tests.py for them
463

    
464
    @staticmethod
465
    def _parsePing( pingOutput ):
466
        "Parse ping output and return packets sent, received."
467
        # Check for downed link
468
        if 'connect: Network is unreachable' in pingOutput:
469
            return 1, 0
470
        r = r'(\d+) packets transmitted, (\d+) received'
471
        m = re.search( r, pingOutput )
472
        if m is None:
473
            error( '*** Error: could not parse ping output: %s\n' %
474
                   pingOutput )
475
            return 1, 0
476
        sent, received = int( m.group( 1 ) ), int( m.group( 2 ) )
477
        return sent, received
478

    
479
    def ping( self, hosts=None, timeout=None ):
480
        """Ping between all specified hosts.
481
           hosts: list of hosts
482
           timeout: time to wait for a response, as string
483
           returns: ploss packet loss percentage"""
484
        # should we check if running?
485
        packets = 0
486
        lost = 0
487
        ploss = None
488
        if not hosts:
489
            hosts = self.hosts
490
            output( '*** Ping: testing ping reachability\n' )
491
        for node in hosts:
492
            output( '%s -> ' % node.name )
493
            for dest in hosts:
494
                if node != dest:
495
                    opts = ''
496
                    if timeout:
497
                        opts = '-W %s' % timeout
498
                    result = node.cmd( 'ping -c1 %s %s' % (opts, dest.IP()) )
499
                    sent, received = self._parsePing( result )
500
                    packets += sent
501
                    if received > sent:
502
                        error( '*** Error: received too many packets' )
503
                        error( '%s' % result )
504
                        node.cmdPrint( 'route' )
505
                        exit( 1 )
506
                    lost += sent - received
507
                    output( ( '%s ' % dest.name ) if received else 'X ' )
508
            output( '\n' )
509
        if packets > 0:
510
            ploss = 100.0 * lost / packets
511
            received = packets - lost
512
            output( "*** Results: %i%% dropped (%d/%d received)\n" %
513
                    ( ploss, received, packets ) )
514
        else:
515
            ploss = 0
516
            output( "*** Warning: No packets sent\n" )
517
        return ploss
518

    
519
    @staticmethod
520
    def _parsePingFull( pingOutput ):
521
        "Parse ping output and return all data."
522
        errorTuple = (1, 0, 0, 0, 0, 0)
523
        # Check for downed link
524
        r = r'[uU]nreachable'
525
        m = re.search( r, pingOutput )
526
        if m is not None:
527
            return errorTuple
528
        r = r'(\d+) packets transmitted, (\d+) received'
529
        m = re.search( r, pingOutput )
530
        if m is None:
531
            error( '*** Error: could not parse ping output: %s\n' %
532
                   pingOutput )
533
            return errorTuple
534
        sent, received = int( m.group( 1 ) ), int( m.group( 2 ) )
535
        r = r'rtt min/avg/max/mdev = '
536
        r += r'(\d+\.\d+)/(\d+\.\d+)/(\d+\.\d+)/(\d+\.\d+) ms'
537
        m = re.search( r, pingOutput )
538
        if m is None:
539
            error( '*** Error: could not parse ping output: %s\n' %
540
                   pingOutput )
541
            return errorTuple
542
        rttmin = float( m.group( 1 ) )
543
        rttavg = float( m.group( 2 ) )
544
        rttmax = float( m.group( 3 ) )
545
        rttdev = float( m.group( 4 ) )
546
        return sent, received, rttmin, rttavg, rttmax, rttdev
547

    
548
    def pingFull( self, hosts=None, timeout=None ):
549
        """Ping between all specified hosts and return all data.
550
           hosts: list of hosts
551
           timeout: time to wait for a response, as string
552
           returns: all ping data; see function body."""
553
        # should we check if running?
554
        # Each value is a tuple: (src, dsd, [all ping outputs])
555
        all_outputs = []
556
        if not hosts:
557
            hosts = self.hosts
558
            output( '*** Ping: testing ping reachability\n' )
559
        for node in hosts:
560
            output( '%s -> ' % node.name )
561
            for dest in hosts:
562
                if node != dest:
563
                    opts = ''
564
                    if timeout:
565
                        opts = '-W %s' % timeout
566
                    result = node.cmd( 'ping -c1 %s %s' % (opts, dest.IP()) )
567
                    outputs = self._parsePingFull( result )
568
                    sent, received, rttmin, rttavg, rttmax, rttdev = outputs
569
                    all_outputs.append( (node, dest, outputs) )
570
                    output( ( '%s ' % dest.name ) if received else 'X ' )
571
            output( '\n' )
572
        output( "*** Results: \n" )
573
        for outputs in all_outputs:
574
            src, dest, ping_outputs = outputs
575
            sent, received, rttmin, rttavg, rttmax, rttdev = ping_outputs
576
            output( " %s->%s: %s/%s, " % (src, dest, sent, received ) )
577
            output( "rtt min/avg/max/mdev %0.3f/%0.3f/%0.3f/%0.3f ms\n" %
578
                    (rttmin, rttavg, rttmax, rttdev) )
579
        return all_outputs
580

    
581
    def pingAll( self, timeout=None ):
582
        """Ping between all hosts.
583
           returns: ploss packet loss percentage"""
584
        return self.ping( timeout=timeout )
585

    
586
    def pingPair( self ):
587
        """Ping between first two hosts, useful for testing.
588
           returns: ploss packet loss percentage"""
589
        hosts = [ self.hosts[ 0 ], self.hosts[ 1 ] ]
590
        return self.ping( hosts=hosts )
591

    
592
    def pingAllFull( self ):
593
        """Ping between all hosts.
594
           returns: ploss packet loss percentage"""
595
        return self.pingFull()
596

    
597
    def pingPairFull( self ):
598
        """Ping between first two hosts, useful for testing.
599
           returns: ploss packet loss percentage"""
600
        hosts = [ self.hosts[ 0 ], self.hosts[ 1 ] ]
601
        return self.pingFull( hosts=hosts )
602

    
603
    @staticmethod
604
    def _parseIperf( iperfOutput ):
605
        """Parse iperf output and return bandwidth.
606
           iperfOutput: string
607
           returns: result string"""
608
        r = r'([\d\.]+ \w+/sec)'
609
        m = re.findall( r, iperfOutput )
610
        if m:
611
            return m[-1]
612
        else:
613
            # was: raise Exception(...)
614
            error( 'could not parse iperf output: ' + iperfOutput )
615
            return ''
616

    
617
    # XXX This should be cleaned up
618

    
619
    def iperf( self, hosts=None, l4Type='TCP', udpBw='10M' ):
620
        """Run iperf between two hosts.
621
           hosts: list of hosts; if None, uses opposite hosts
622
           l4Type: string, one of [ TCP, UDP ]
623
           returns: results two-element array of server and client speeds"""
624
        if not quietRun( 'which telnet' ):
625
            error( 'Cannot find telnet in $PATH - required for iperf test' )
626
            return
627
        if not hosts:
628
            hosts = [ self.hosts[ 0 ], self.hosts[ -1 ] ]
629
        else:
630
            assert len( hosts ) == 2
631
        client, server = hosts
632
        output( '*** Iperf: testing ' + l4Type + ' bandwidth between ' )
633
        output( "%s and %s\n" % ( client.name, server.name ) )
634
        server.cmd( 'killall -9 iperf' )
635
        iperfArgs = 'iperf '
636
        bwArgs = ''
637
        if l4Type == 'UDP':
638
            iperfArgs += '-u '
639
            bwArgs = '-b ' + udpBw + ' '
640
        elif l4Type != 'TCP':
641
            raise Exception( 'Unexpected l4 type: %s' % l4Type )
642
        server.sendCmd( iperfArgs + '-s', printPid=True )
643
        servout = ''
644
        while server.lastPid is None:
645
            servout += server.monitor()
646
        if l4Type == 'TCP':
647
            while 'Connected' not in client.cmd(
648
                    'sh -c "echo A | telnet -e A %s 5001"' % server.IP()):
649
                output('waiting for iperf to start up...')
650
                sleep(.5)
651
        cliout = client.cmd( iperfArgs + '-t 5 -c ' + server.IP() + ' ' +
652
                             bwArgs )
653
        debug( 'Client output: %s\n' % cliout )
654
        server.sendInt()
655
        servout += server.waitOutput()
656
        debug( 'Server output: %s\n' % servout )
657
        result = [ self._parseIperf( servout ), self._parseIperf( cliout ) ]
658
        if l4Type == 'UDP':
659
            result.insert( 0, udpBw )
660
        output( '*** Results: %s\n' % result )
661
        return result
662

    
663
    def runCpuLimitTest( self, cpu, duration=5 ):
664
        """run CPU limit test with 'while true' processes.
665
        cpu: desired CPU fraction of each host
666
        duration: test duration in seconds
667
        returns a single list of measured CPU fractions as floats.
668
        """
669
        pct = cpu * 100
670
        info('*** Testing CPU %.0f%% bandwidth limit\n' % pct)
671
        hosts = self.hosts
672
        for h in hosts:
673
            h.cmd( 'while true; do a=1; done &' )
674
        pids = [h.cmd( 'echo $!' ).strip() for h in hosts]
675
        pids_str = ",".join(["%s" % pid for pid in pids])
676
        cmd = 'ps -p %s -o pid,%%cpu,args' % pids_str
677
        # It's a shame that this is what pylint prefers
678
        outputs = []
679
        for _ in range( duration ):
680
            sleep( 1 )
681
            outputs.append( quietRun( cmd ).strip() )
682
        for h in hosts:
683
            h.cmd( 'kill %1' )
684
        cpu_fractions = []
685
        for test_output in outputs:
686
            # Split by line.  Ignore first line, which looks like this:
687
            # PID %CPU COMMAND\n
688
            for line in test_output.split('\n')[1:]:
689
                r = r'\d+\s*(\d+\.\d+)'
690
                m = re.search( r, line )
691
                if m is None:
692
                    error( '*** Error: could not extract CPU fraction: %s\n' %
693
                           line )
694
                    return None
695
                cpu_fractions.append( float( m.group( 1 ) ) )
696
        output( '*** Results: %s\n' % cpu_fractions )
697
        return cpu_fractions
698

    
699
    # BL: I think this can be rewritten now that we have
700
    # a real link class.
701
    def configLinkStatus( self, src, dst, status ):
702
        """Change status of src <-> dst links.
703
           src: node name
704
           dst: node name
705
           status: string {up, down}"""
706
        if src not in self.nameToNode:
707
            error( 'src not in network: %s\n' % src )
708
        elif dst not in self.nameToNode:
709
            error( 'dst not in network: %s\n' % dst )
710
        else:
711
            if type( src ) is str:
712
                src = self.nameToNode[ src ]
713
            if type( dst ) is str:
714
                dst = self.nameToNode[ dst ]
715
            connections = src.connectionsTo( dst )
716
            if len( connections ) == 0:
717
                error( 'src and dst not connected: %s %s\n' % ( src, dst) )
718
            for srcIntf, dstIntf in connections:
719
                result = srcIntf.ifconfig( status )
720
                if result:
721
                    error( 'link src status change failed: %s\n' % result )
722
                result = dstIntf.ifconfig( status )
723
                if result:
724
                    error( 'link dst status change failed: %s\n' % result )
725

    
726
    def interact( self ):
727
        "Start network and run our simple CLI."
728
        self.start()
729
        result = CLI( self )
730
        self.stop()
731
        return result
732

    
733
    inited = False
734

    
735
    @classmethod
736
    def init( cls ):
737
        "Initialize Mininet"
738
        if cls.inited:
739
            return
740
        ensureRoot()
741
        fixLimits()
742
        cls.inited = True
743

    
744

    
745
class MininetWithControlNet( Mininet ):
746

    
747
    """Control network support:
748

749
       Create an explicit control network. Currently this is only
750
       used/usable with the user datapath.
751

752
       Notes:
753

754
       1. If the controller and switches are in the same (e.g. root)
755
          namespace, they can just use the loopback connection.
756

757
       2. If we can get unix domain sockets to work, we can use them
758
          instead of an explicit control network.
759

760
       3. Instead of routing, we could bridge or use 'in-band' control.
761

762
       4. Even if we dispense with this in general, it could still be
763
          useful for people who wish to simulate a separate control
764
          network (since real networks may need one!)
765

766
       5. Basically nobody ever used this code, so it has been moved
767
          into its own class.
768

769
       6. Ultimately we may wish to extend this to allow us to create a
770
          control network which every node's control interface is
771
          attached to."""
772

    
773
    def configureControlNetwork( self ):
774
        "Configure control network."
775
        self.configureRoutedControlNetwork()
776

    
777
    # We still need to figure out the right way to pass
778
    # in the control network location.
779

    
780
    def configureRoutedControlNetwork( self, ip='192.168.123.1',
781
                                       prefixLen=16 ):
782
        """Configure a routed control network on controller and switches.
783
           For use with the user datapath only right now."""
784
        controller = self.controllers[ 0 ]
785
        info( controller.name + ' <->' )
786
        cip = ip
787
        snum = ipParse( ip )
788
        for switch in self.switches:
789
            info( ' ' + switch.name )
790
            link = self.link( switch, controller, port1=0 )
791
            sintf, cintf = link.intf1, link.intf2
792
            switch.controlIntf = sintf
793
            snum += 1
794
            while snum & 0xff in [ 0, 255 ]:
795
                snum += 1
796
            sip = ipStr( snum )
797
            cintf.setIP( cip, prefixLen )
798
            sintf.setIP( sip, prefixLen )
799
            controller.setHostRoute( sip, cintf )
800
            switch.setHostRoute( cip, sintf )
801
        info( '\n' )
802
        info( '*** Testing control network\n' )
803
        while not cintf.isUp():
804
            info( '*** Waiting for', cintf, 'to come up\n' )
805
            sleep( 1 )
806
        for switch in self.switches:
807
            while not sintf.isUp():
808
                info( '*** Waiting for', sintf, 'to come up\n' )
809
                sleep( 1 )
810
            if self.ping( hosts=[ switch, controller ] ) != 0:
811
                error( '*** Error: control network test failed\n' )
812
                exit( 1 )
813
        info( '\n' )