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"""
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    Mininet: A simple networking testbed for OpenFlow/SDN!
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author: Bob Lantz (rlantz@cs.stanford.edu)
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author: Brandon Heller (brandonh@stanford.edu)
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Mininet creates scalable OpenFlow test networks by using
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process-based virtualization and network namespaces.
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Simulated hosts are created as processes in separate network
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namespaces. This allows a complete OpenFlow network to be simulated on
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top of a single Linux kernel.
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Each host has:
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A virtual console (pipes to a shell)
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A virtual interfaces (half of a veth pair)
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A parent shell (and possibly some child processes) in a namespace
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Hosts have a network interface which is configured via ifconfig/ip
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link/etc.
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This version supports both the kernel and user space datapaths
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from the OpenFlow reference implementation (openflowswitch.org)
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as well as OpenVSwitch (openvswitch.org.)
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In kernel datapath mode, the controller and switches are simply
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processes in the root namespace.
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Kernel OpenFlow datapaths are instantiated using dpctl(8), and are
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attached to the one side of a veth pair; the other side resides in the
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host namespace. In this mode, switch processes can simply connect to the
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controller via the loopback interface.
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In user datapath mode, the controller and switches can be full-service
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nodes that live in their own network namespaces and have management
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interfaces and IP addresses on a control network (e.g. 192.168.123.1,
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currently routed although it could be bridged.)
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In addition to a management interface, user mode switches also have
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several switch interfaces, halves of veth pairs whose other halves
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reside in the host nodes that the switches are connected to.
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Consistent, straightforward naming is important in order to easily
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identify hosts, switches and controllers, both from the CLI and
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from program code. Interfaces are named to make it easy to identify
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which interfaces belong to which node.
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The basic naming scheme is as follows:
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    Host nodes are named h1-hN
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    Switch nodes are named s1-sN
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    Controller nodes are named c0-cN
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    Interfaces are named {nodename}-eth0 .. {nodename}-ethN
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Note: If the network topology is created using mininet.topo, then
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node numbers are unique among hosts and switches (e.g. we have
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h1..hN and SN..SN+M) and also correspond to their default IP addresses
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of 10.x.y.z/8 where x.y.z is the base-256 representation of N for
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hN. This mapping allows easy determination of a node's IP
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address from its name, e.g. h1 -> 10.0.0.1, h257 -> 10.0.1.1.
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Note also that 10.0.0.1 can often be written as 10.1 for short, e.g.
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"ping 10.1" is equivalent to "ping 10.0.0.1".
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Currently we wrap the entire network in a 'mininet' object, which
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constructs a simulated network based on a network topology created
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using a topology object (e.g. LinearTopo) from mininet.topo or
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mininet.topolib, and a Controller which the switches will connect
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to. Several configuration options are provided for functions such as
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automatically setting MAC addresses, populating the ARP table, or
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even running a set of terminals to allow direct interaction with nodes.
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After the network is created, it can be started using start(), and a
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variety of useful tasks maybe performed, including basic connectivity
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and bandwidth tests and running the mininet CLI.
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Once the network is up and running, test code can easily get access
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to host and switch objects which can then be used for arbitrary
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experiments, typically involving running a series of commands on the
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hosts.
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After all desired tests or activities have been completed, the stop()
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method may be called to shut down the network.
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"""
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import os
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import re
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import select
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import signal
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import random
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import copy
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from time import sleep
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from itertools import chain, groupby
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from math import ceil
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from mininet.cli import CLI
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from mininet.log import info, error, debug, output, warn
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from mininet.node import Host, OVSKernelSwitch, DefaultController, Controller
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from mininet.nodelib import NAT
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from mininet.link import Link, Intf
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from mininet.util import quietRun, fixLimits, numCores, ensureRoot
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from mininet.util import macColonHex, ipStr, ipParse, netParse, ipAdd
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from mininet.term import cleanUpScreens, makeTerms
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# Mininet version: should be consistent with README and LICENSE
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VERSION = "2.2.0b1"
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class Mininet( object ):
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    "Network emulation with hosts spawned in network namespaces."
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    def __init__( self, topo=None, switch=OVSKernelSwitch, host=Host,
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                  controller=DefaultController, link=Link, intf=Intf,
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                  build=True, xterms=False, cleanup=False, ipBase='10.0.0.0/8',
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                  inNamespace=False,
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                  autoSetMacs=False, autoStaticArp=False, autoPinCpus=False,
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                  listenPort=None, waitConnected=False ):
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        """Create Mininet object.
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           topo: Topo (topology) object or None
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           switch: default Switch class
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           host: default Host class/constructor
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           controller: default Controller class/constructor
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           link: default Link class/constructor
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           intf: default Intf class/constructor
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           ipBase: base IP address for hosts,
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           build: build now from topo?
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           xterms: if build now, spawn xterms?
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           cleanup: if build now, cleanup before creating?
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           inNamespace: spawn switches and controller in net namespaces?
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           autoSetMacs: set MAC addrs automatically like IP addresses?
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           autoStaticArp: set all-pairs static MAC addrs?
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           autoPinCpus: pin hosts to (real) cores (requires CPULimitedHost)?
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           listenPort: base listening port to open; will be incremented for
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               each additional switch in the net if inNamespace=False"""
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        self.topo = topo
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        self.switch = switch
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        self.host = host
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        self.controller = controller
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        self.link = link
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        self.intf = intf
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        self.ipBase = ipBase
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        self.ipBaseNum, self.prefixLen = netParse( self.ipBase )
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        self.nextIP = 1  # start for address allocation
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        self.inNamespace = inNamespace
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        self.xterms = xterms
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        self.cleanup = cleanup
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        self.autoSetMacs = autoSetMacs
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        self.autoStaticArp = autoStaticArp
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        self.autoPinCpus = autoPinCpus
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        self.numCores = numCores()
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        self.nextCore = 0  # next core for pinning hosts to CPUs
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        self.listenPort = listenPort
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        self.waitConn = waitConnected
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        self.hosts = []
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        self.switches = []
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        self.controllers = []
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        self.links = []
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        self.nameToNode = {}  # name to Node (Host/Switch) objects
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        self.terms = []  # list of spawned xterm processes
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        Mininet.init()  # Initialize Mininet if necessary
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        self.built = False
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        if topo and build:
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            self.build()
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    def waitConnected( self, timeout=None, delay=.5 ):
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        """wait for each switch to connect to a controller,
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           up to 5 seconds
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           timeout: time to wait, or None to wait indefinitely
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           delay: seconds to sleep per iteration
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           returns: True if all switches are connected"""
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        info( '*** Waiting for switches to connect\n' )
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        time = 0
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        remaining = list( self.switches )
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        while True:
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            for switch in tuple( remaining ):
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                if switch.connected():
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                    info( '%s ' % switch )
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                    remaining.remove( switch )
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            if not remaining:
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                info( '\n' )
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                return True
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            if time > timeout and timeout is not None:
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                break
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            sleep( delay )
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            time += delay
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        warn( 'Timed out after %d seconds\n' % time )
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        for switch in remaining:
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            if not switch.connected():
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                warn( 'Warning: %s is not connected to a controller\n'
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                      % switch.name )
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            else:
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                remaining.remove( switch )
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        return not remaining
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    def addHost( self, name, cls=None, **params ):
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        """Add host.
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           name: name of host to add
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           cls: custom host class/constructor (optional)
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           params: parameters for host
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           returns: added host"""
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        # Default IP and MAC addresses
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        defaults = { 'ip': ipAdd( self.nextIP,
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                                  ipBaseNum=self.ipBaseNum,
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                                  prefixLen=self.prefixLen ) +
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                                  '/%s' % self.prefixLen }
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        if self.autoSetMacs:
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            defaults[ 'mac' ] = macColonHex( self.nextIP )
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        if self.autoPinCpus:
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            defaults[ 'cores' ] = self.nextCore
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            self.nextCore = ( self.nextCore + 1 ) % self.numCores
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        self.nextIP += 1
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        defaults.update( params )
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        if not cls:
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            cls = self.host
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        h = cls( name, **defaults )
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        self.hosts.append( h )
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        self.nameToNode[ name ] = h
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        return h
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    def addSwitch( self, name, cls=None, **params ):
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        """Add switch.
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           name: name of switch to add
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           cls: custom switch class/constructor (optional)
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           returns: added switch
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           side effect: increments listenPort ivar ."""
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        defaults = { 'listenPort': self.listenPort,
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                     'inNamespace': self.inNamespace }
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        defaults.update( params )
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        if not cls:
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            cls = self.switch
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        sw = cls( name, **defaults )
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        if not self.inNamespace and self.listenPort:
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            self.listenPort += 1
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        self.switches.append( sw )
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        self.nameToNode[ name ] = sw
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        return sw
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    def addController( self, name='c0', controller=None, **params ):
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        """Add controller.
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           controller: Controller class"""
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        # Get controller class
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        if not controller:
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            controller = self.controller
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        # Construct new controller if one is not given
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        if isinstance( name, Controller ):
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            controller_new = name
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            # Pylint thinks controller is a str()
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            # pylint: disable=E1103
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            name = controller_new.name
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            # pylint: enable=E1103
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        else:
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            controller_new = controller( name, **params )
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        # Add new controller to net
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        if controller_new: # allow controller-less setups
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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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    def addNAT( self, name='nat0', connect=True, inNamespace=False, **params ):
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        nat = self.addHost( name, cls=NAT, inNamespace=inNamespace, 
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                            subnet=self.ipBase, **params )
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        # find first switch and create link
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        if connect:
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            # connect the nat to the first switch
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            self.addLink( nat, self.switches[ 0 ] )
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            # set the default route on hosts
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            natIP = nat.params[ 'ip' ].split('/')[ 0 ]
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            for host in self.hosts:
277
                if host.inNamespace:
278
                    host.setDefaultRoute( 'via %s' % natIP )
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        return nat
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281
    # BL: We now have four ways to look up nodes
282
    # This may (should?) be cleaned up in the future.
283
    def getNodeByName( self, *args ):
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        "Return node(s) with given name(s)"
285
        if len( args ) == 1:
286
            return self.nameToNode[ args[ 0 ] ]
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        return [ self.nameToNode[ n ] for n in args ]
288

    
289
    def get( self, *args ):
290
        "Convenience alias for getNodeByName"
291
        return self.getNodeByName( *args )
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293
    # Even more convenient syntax for node lookup and iteration
294
    def __getitem__( self, key ):
295
        """net [ name ] operator: Return node(s) with given name(s)"""
296
        return self.nameToNode[ key ]
297

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

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

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

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

    
316
    def values( self ):
317
        "return a list of all nodes or net's values"
318
        return [ self[name] for name in self ]
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320
    def items( self ):
321
        "return (key,value) tuple list for every node in net"
322
        return zip( self.keys(), self.values() )
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324
    @staticmethod
325
    def randMac():
326
        "Return a random, non-multicast MAC address"
327
        return macColonHex( random.randint(1, 2**48 - 1) & 0xfeffffffffff  |
328
                            0x020000000000 )
329
    
330
    def addLink( self, node1, node2, port1=None, port2=None,
331
                 cls=None, **params ):
332
        """"Add a link from node1 to node2
333
            node1: source node (or name)
334
            node2: dest node (or name)
335
            port1: source port (optional)
336
            port2: dest port (optional)
337
            cls: link class (optional)
338
            params: additional link params (optional)
339
            returns: link object"""
340
        # Accept node objects or names
341
        node1 = node1 if type( node1 ) != str else self[ node1 ]
342
        node2 = node2 if type( node2 ) != str else self[ node2 ]
343
        options = dict( params )
344
        # Port is optional
345
        if port1 is not None:
346
            options.setdefault( 'port1', port1 )
347
        if port2 is not None:
348
            options.setdefault( 'port2', port2 )
349
        # Set default MAC - this should probably be in Link
350
        options.setdefault( 'addr1', self.randMac() )
351
        options.setdefault( 'addr2', self.randMac() )
352
        cls = self.link if cls is None else cls
353
        link = cls( node1, node2, **options )
354
        self.links.append( link )
355
        return link
356

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

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

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

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

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

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

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

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

    
416
        info( '\n' )
417

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

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

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

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

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

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

    
476
    def stop( self ):
477
        "Stop the controller(s), switches and hosts"
478
        info( '*** Stopping %i controllers\n' % len( self.controllers ) )
479
        for controller in self.controllers:
480
            info( controller.name + ' ' )
481
            controller.stop()
482
        info( '\n' )
483
        if self.terms:
484
            info( '*** Stopping %i terms\n' % len( self.terms ) )
485
            self.stopXterms()
486
        info( '*** Stopping %i switches\n' % len( self.switches ) )
487
        for swclass, switches in groupby( sorted( self.switches, key=type ), type ):
488
            if hasattr( swclass, 'batchShutdown' ):
489
                swclass.batchShutdown( switches )
490
        for switch in self.switches:
491
            info( switch.name + ' ' )
492
            switch.stop()
493
            switch.terminate()
494
        info( '\n' )
495
        info( '*** Stopping %i links\n' % len( self.links ) )
496
        for link in self.links:
497
            link.stop()
498
        info( '\n' )
499
        info( '*** Stopping %i hosts\n' % len( self.hosts ) )
500
        for host in self.hosts:
501
            info( host.name + ' ' )
502
            host.terminate()
503
        info( '\n*** Done\n' )
504

    
505
    def run( self, test, *args, **kwargs ):
506
        "Perform a complete start/test/stop cycle."
507
        self.start()
508
        info( '*** Running test\n' )
509
        result = test( *args, **kwargs )
510
        self.stop()
511
        return result
512

    
513
    def monitor( self, hosts=None, timeoutms=-1 ):
514
        """Monitor a set of hosts (or all hosts by default),
515
           and return their output, a line at a time.
516
           hosts: (optional) set of hosts to monitor
517
           timeoutms: (optional) timeout value in ms
518
           returns: iterator which returns host, line"""
519
        if hosts is None:
520
            hosts = self.hosts
521
        poller = select.poll()
522
        Node = hosts[ 0 ]  # so we can call class method fdToNode
523
        for host in hosts:
524
            poller.register( host.stdout )
525
        while True:
526
            ready = poller.poll( timeoutms )
527
            for fd, event in ready:
528
                host = Node.fdToNode( fd )
529
                if event & select.POLLIN:
530
                    line = host.readline()
531
                    if line is not None:
532
                        yield host, line
533
            # Return if non-blocking
534
            if not ready and timeoutms >= 0:
535
                yield None, None
536

    
537
    # XXX These test methods should be moved out of this class.
538
    # Probably we should create a tests.py for them
539

    
540
    @staticmethod
541
    def _parsePing( pingOutput ):
542
        "Parse ping output and return packets sent, received."
543
        # Check for downed link
544
        if 'connect: Network is unreachable' in pingOutput:
545
            return 1, 0
546
        r = r'(\d+) packets transmitted, (\d+) received'
547
        m = re.search( r, pingOutput )
548
        if m is None:
549
            error( '*** Error: could not parse ping output: %s\n' %
550
                   pingOutput )
551
            return 1, 0
552
        sent, received = int( m.group( 1 ) ), int( m.group( 2 ) )
553
        return sent, received
554

    
555
    def ping( self, hosts=None, timeout=None ):
556
        """Ping between all specified hosts.
557
           hosts: list of hosts
558
           timeout: time to wait for a response, as string
559
           returns: ploss packet loss percentage"""
560
        # should we check if running?
561
        packets = 0
562
        lost = 0
563
        ploss = None
564
        if not hosts:
565
            hosts = self.hosts
566
            output( '*** Ping: testing ping reachability\n' )
567
        for node in hosts:
568
            output( '%s -> ' % node.name )
569
            for dest in hosts:
570
                if node != dest:
571
                    opts = ''
572
                    if timeout:
573
                        opts = '-W %s' % timeout
574
                    if dest.intfs:
575
                        result = node.cmd( 'ping -c1 %s %s' % (opts, dest.IP()) )
576
                        sent, received = self._parsePing( result )
577
                    else:
578
                        sent, received = 0, 0
579
                    packets += sent
580
                    if received > sent:
581
                        error( '*** Error: received too many packets' )
582
                        error( '%s' % result )
583
                        node.cmdPrint( 'route' )
584
                        exit( 1 )
585
                    lost += sent - received
586
                    output( ( '%s ' % dest.name ) if received else 'X ' )
587
            output( '\n' )
588
        if packets > 0:
589
            ploss = 100.0 * lost / packets
590
            received = packets - lost
591
            output( "*** Results: %i%% dropped (%d/%d received)\n" %
592
                    ( ploss, received, packets ) )
593
        else:
594
            ploss = 0
595
            output( "*** Warning: No packets sent\n" )
596
        return ploss
597

    
598
    @staticmethod
599
    def _parsePingFull( pingOutput ):
600
        "Parse ping output and return all data."
601
        errorTuple = (1, 0, 0, 0, 0, 0)
602
        # Check for downed link
603
        r = r'[uU]nreachable'
604
        m = re.search( r, pingOutput )
605
        if m is not None:
606
            return errorTuple
607
        r = r'(\d+) packets transmitted, (\d+) received'
608
        m = re.search( r, pingOutput )
609
        if m is None:
610
            error( '*** Error: could not parse ping output: %s\n' %
611
                   pingOutput )
612
            return errorTuple
613
        sent, received = int( m.group( 1 ) ), int( m.group( 2 ) )
614
        r = r'rtt min/avg/max/mdev = '
615
        r += r'(\d+\.\d+)/(\d+\.\d+)/(\d+\.\d+)/(\d+\.\d+) ms'
616
        m = re.search( r, pingOutput )
617
        if m is None:
618
            if received == 0:
619
                return errorTuple
620
            error( '*** Error: could not parse ping output: %s\n' %
621
                   pingOutput )
622
            return errorTuple
623
        rttmin = float( m.group( 1 ) )
624
        rttavg = float( m.group( 2 ) )
625
        rttmax = float( m.group( 3 ) )
626
        rttdev = float( m.group( 4 ) )
627
        return sent, received, rttmin, rttavg, rttmax, rttdev
628

    
629
    def pingFull( self, hosts=None, timeout=None ):
630
        """Ping between all specified hosts and return all data.
631
           hosts: list of hosts
632
           timeout: time to wait for a response, as string
633
           returns: all ping data; see function body."""
634
        # should we check if running?
635
        # Each value is a tuple: (src, dsd, [all ping outputs])
636
        all_outputs = []
637
        if not hosts:
638
            hosts = self.hosts
639
            output( '*** Ping: testing ping reachability\n' )
640
        for node in hosts:
641
            output( '%s -> ' % node.name )
642
            for dest in hosts:
643
                if node != dest:
644
                    opts = ''
645
                    if timeout:
646
                        opts = '-W %s' % timeout
647
                    result = node.cmd( 'ping -c1 %s %s' % (opts, dest.IP()) )
648
                    outputs = self._parsePingFull( result )
649
                    sent, received, rttmin, rttavg, rttmax, rttdev = outputs
650
                    all_outputs.append( (node, dest, outputs) )
651
                    output( ( '%s ' % dest.name ) if received else 'X ' )
652
            output( '\n' )
653
        output( "*** Results: \n" )
654
        for outputs in all_outputs:
655
            src, dest, ping_outputs = outputs
656
            sent, received, rttmin, rttavg, rttmax, rttdev = ping_outputs
657
            output( " %s->%s: %s/%s, " % (src, dest, sent, received ) )
658
            output( "rtt min/avg/max/mdev %0.3f/%0.3f/%0.3f/%0.3f ms\n" %
659
                    (rttmin, rttavg, rttmax, rttdev) )
660
        return all_outputs
661

    
662
    def pingAll( self, timeout=None ):
663
        """Ping between all hosts.
664
           returns: ploss packet loss percentage"""
665
        return self.ping( timeout=timeout )
666

    
667
    def pingPair( self ):
668
        """Ping between first two hosts, useful for testing.
669
           returns: ploss packet loss percentage"""
670
        hosts = [ self.hosts[ 0 ], self.hosts[ 1 ] ]
671
        return self.ping( hosts=hosts )
672

    
673
    def pingAllFull( self ):
674
        """Ping between all hosts.
675
           returns: ploss packet loss percentage"""
676
        return self.pingFull()
677

    
678
    def pingPairFull( self ):
679
        """Ping between first two hosts, useful for testing.
680
           returns: ploss packet loss percentage"""
681
        hosts = [ self.hosts[ 0 ], self.hosts[ 1 ] ]
682
        return self.pingFull( hosts=hosts )
683

    
684
    @staticmethod
685
    def _parseIperf( iperfOutput ):
686
        """Parse iperf output and return bandwidth.
687
           iperfOutput: string
688
           returns: result string"""
689
        r = r'([\d\.]+ \w+/sec)'
690
        m = re.findall( r, iperfOutput )
691
        if m:
692
            return m[-1]
693
        else:
694
            # was: raise Exception(...)
695
            error( 'could not parse iperf output: ' + iperfOutput )
696
            return ''
697

    
698
    # XXX This should be cleaned up
699

    
700
    def iperf( self, hosts=None, l4Type='TCP', udpBw='10M', format=None,
701
               seconds=5):
702
        """Run iperf between two hosts.
703
           hosts: list of hosts; if None, uses opposite hosts
704
           l4Type: string, one of [ TCP, UDP ]
705
           udpBw: bandwidth target for UDP test
706
           format: iperf format argument if any
707
           seconds: iperf time to transmit
708
           returns: two-element array of [ server, client ] speeds
709
           note: send() is buffered, so client rate can be much higher than
710
           the actual transmission rate; on an unloaded system, server
711
           rate should be much closer to the actual receive rate"""
712
        if not quietRun( 'which telnet' ):
713
            error( 'Cannot find telnet in $PATH - required for iperf test' )
714
            return
715
        if not hosts:
716
            hosts = [ self.hosts[ 0 ], self.hosts[ -1 ] ]
717
        else:
718
            assert len( hosts ) == 2
719
        client, server = hosts
720
        output( '*** Iperf: testing ' + l4Type + ' bandwidth between ' )
721
        output( "%s and %s\n" % ( client.name, server.name ) )
722
        server.cmd( 'killall -9 iperf' )
723
        iperfArgs = 'iperf '
724
        bwArgs = ''
725
        if l4Type == 'UDP':
726
            iperfArgs += '-u '
727
            bwArgs = '-b ' + udpBw + ' '
728
        elif l4Type != 'TCP':
729
            raise Exception( 'Unexpected l4 type: %s' % l4Type )
730
        if format:
731
          iperfArgs += '-f %s ' %format
732
        server.sendCmd( iperfArgs + '-s', printPid=True )
733
        servout = ''
734
        while server.lastPid is None:
735
            servout += server.monitor()
736
        if l4Type == 'TCP':
737
            while 'Connected' not in client.cmd(
738
                    'sh -c "echo A | telnet -e A %s 5001"' % server.IP()):
739
                info( 'Waiting for iperf to start up...' )
740
                sleep(.5)
741
        cliout = client.cmd( iperfArgs + '-t %d -c ' % seconds +
742
                             server.IP() + ' ' + bwArgs )
743
        debug( 'Client output: %s\n' % cliout )
744
        server.sendInt()
745
        servout += server.waitOutput()
746
        debug( 'Server output: %s\n' % servout )
747
        result = [ self._parseIperf( servout ), self._parseIperf( cliout ) ]
748
        if l4Type == 'UDP':
749
            result.insert( 0, udpBw )
750
        output( '*** Results: %s\n' % result )
751
        return result
752

    
753
    def runCpuLimitTest( self, cpu, duration=5 ):
754
        """run CPU limit test with 'while true' processes.
755
        cpu: desired CPU fraction of each host
756
        duration: test duration in seconds
757
        returns a single list of measured CPU fractions as floats.
758
        """
759
        cores = int( quietRun( 'nproc' ) )
760
        pct = cpu * 100
761
        info( '*** Testing CPU %.0f%% bandwidth limit\n' % pct )
762
        hosts = self.hosts
763
        cores = int( quietRun( 'nproc' ) )
764
        # number of processes to run a while loop on per host
765
        num_procs = int( ceil( cores * cpu ) )
766
        pids = {}
767
        for h in hosts:
768
            pids[ h ] = []
769
            for _core in range( num_procs ):
770
                h.cmd( 'while true; do a=1; done &' )
771
                pids[ h ].append( h.cmd( 'echo $!' ).strip() )
772
        outputs = {}
773
        time = {}
774
        # get the initial cpu time for each host
775
        for host in hosts:
776
            outputs[ host ] = []
777
            with open( '/sys/fs/cgroup/cpuacct/%s/cpuacct.usage' % host, 'r' ) as f:
778
                time[ host ] = float( f.read() )
779
        for _ in range( 5 ):
780
            sleep( 1 )
781
            for host in hosts:
782
                with open( '/sys/fs/cgroup/cpuacct/%s/cpuacct.usage' % host, 'r' ) as f:
783
                    readTime = float( f.read() )
784
                outputs[ host ].append( ( ( readTime - time[ host ] )
785
                                        / 1000000000 ) / cores * 100 )
786
                time[ host ] = readTime
787
        for h, pids in pids.items():
788
            for pid in pids:
789
                h.cmd( 'kill -9 %s' % pid )
790
        cpu_fractions = []
791
        for _host, outputs in outputs.items():
792
            for pct in outputs:
793
                cpu_fractions.append( pct )
794
        output( '*** Results: %s\n' % cpu_fractions )
795
        return cpu_fractions
796

    
797
    # BL: I think this can be rewritten now that we have
798
    # a real link class.
799
    def configLinkStatus( self, src, dst, status ):
800
        """Change status of src <-> dst links.
801
           src: node name
802
           dst: node name
803
           status: string {up, down}"""
804
        if src not in self.nameToNode:
805
            error( 'src not in network: %s\n' % src )
806
        elif dst not in self.nameToNode:
807
            error( 'dst not in network: %s\n' % dst )
808
        else:
809
            if type( src ) is str:
810
                src = self.nameToNode[ src ]
811
            if type( dst ) is str:
812
                dst = self.nameToNode[ dst ]
813
            connections = src.connectionsTo( dst )
814
            if len( connections ) == 0:
815
                error( 'src and dst not connected: %s %s\n' % ( src, dst) )
816
            for srcIntf, dstIntf in connections:
817
                result = srcIntf.ifconfig( status )
818
                if result:
819
                    error( 'link src status change failed: %s\n' % result )
820
                result = dstIntf.ifconfig( status )
821
                if result:
822
                    error( 'link dst status change failed: %s\n' % result )
823

    
824
    def interact( self ):
825
        "Start network and run our simple CLI."
826
        self.start()
827
        result = CLI( self )
828
        self.stop()
829
        return result
830

    
831
    inited = False
832

    
833
    @classmethod
834
    def init( cls ):
835
        "Initialize Mininet"
836
        if cls.inited:
837
            return
838
        ensureRoot()
839
        fixLimits()
840
        cls.inited = True
841

    
842

    
843
class MininetWithControlNet( Mininet ):
844

    
845
    """Control network support:
846

847
       Create an explicit control network. Currently this is only
848
       used/usable with the user datapath.
849

850
       Notes:
851

852
       1. If the controller and switches are in the same (e.g. root)
853
          namespace, they can just use the loopback connection.
854

855
       2. If we can get unix domain sockets to work, we can use them
856
          instead of an explicit control network.
857

858
       3. Instead of routing, we could bridge or use 'in-band' control.
859

860
       4. Even if we dispense with this in general, it could still be
861
          useful for people who wish to simulate a separate control
862
          network (since real networks may need one!)
863

864
       5. Basically nobody ever used this code, so it has been moved
865
          into its own class.
866

867
       6. Ultimately we may wish to extend this to allow us to create a
868
          control network which every node's control interface is
869
          attached to."""
870

    
871
    def configureControlNetwork( self ):
872
        "Configure control network."
873
        self.configureRoutedControlNetwork()
874

    
875
    # We still need to figure out the right way to pass
876
    # in the control network location.
877

    
878
    def configureRoutedControlNetwork( self, ip='192.168.123.1',
879
                                       prefixLen=16 ):
880
        """Configure a routed control network on controller and switches.
881
           For use with the user datapath only right now."""
882
        controller = self.controllers[ 0 ]
883
        info( controller.name + ' <->' )
884
        cip = ip
885
        snum = ipParse( ip )
886
        for switch in self.switches:
887
            info( ' ' + switch.name )
888
            link = self.link( switch, controller, port1=0 )
889
            sintf, cintf = link.intf1, link.intf2
890
            switch.controlIntf = sintf
891
            snum += 1
892
            while snum & 0xff in [ 0, 255 ]:
893
                snum += 1
894
            sip = ipStr( snum )
895
            cintf.setIP( cip, prefixLen )
896
            sintf.setIP( sip, prefixLen )
897
            controller.setHostRoute( sip, cintf )
898
            switch.setHostRoute( cip, sintf )
899
        info( '\n' )
900
        info( '*** Testing control network\n' )
901
        while not cintf.isUp():
902
            info( '*** Waiting for', cintf, 'to come up\n' )
903
            sleep( 1 )
904
        for switch in self.switches:
905
            while not sintf.isUp():
906
                info( '*** Waiting for', sintf, 'to come up\n' )
907
                sleep( 1 )
908
            if self.ping( hosts=[ switch, controller ] ) != 0:
909
                error( '*** Error: control network test failed\n' )
910
                exit( 1 )
911
        info( '\n' )