8000 mininet/mininet/net.py at devel/add-del · cautonwong/mininet · GitHub
[go: up one dir, main page]
Skip to content

net.py

Latest commit

 

History

History
executable file
·
991 lines (885 loc) · 37.5 KB

net.py

File metadata and controls

executable file
·
991 lines (885 loc) · 37.5 KB
Raw
"""Monitor a set of hosts (or all hosts by default),
and return their output, a line at a time.
hosts: (optional) set of hosts to monitor
timeoutms: (optional) timeout value in ms
returns: iterator which returns host, line"""
if hosts is None:
hosts = self.hosts
poller = select.poll()
h1 = hosts[ 0 ] # so we can call class method fdToNode
for host in hosts:
poller.register( host.stdout )
while True:
ready = poller.poll( timeoutms )
for fd, event in ready:
host = h1.fdToNode( fd )
if event & select.POLLIN:
line = host.readline()
if line is not None:
yield host, line
# Return if non-blocking
if not ready and timeoutms >= 0:
yield None, None
# XXX These test methods should be moved out of this class.
# Probably we should create a tests.py for them
@staticmethod
def _parsePing( pingOutput ):
"Parse ping output and return packets sent, received."
# Check for downed link
if 'connect: Network is unreachable' in pingOutput:
return 1, 0
r = r'(\d+) packets transmitted, (\d+) received'
m = re.search( r, pingOutput )
if m is None:
error( '*** Error: could not parse ping output: %s\n' %
pingOutput )
return 1, 0
sent, received = int( m.group( 1 ) ), int( m.group( 2 ) )
return sent, received
def ping( self, hosts=None, timeout=None ):
"""Ping between all specified hosts.
hosts: list of hosts
timeout: time to wait for a response, as string
returns: ploss packet loss percentage"""
# should we check if running?
packets = 0
lost = 0
ploss = None
if not hosts:
hosts = self.hosts
output( '*** Ping: testing ping reachability\n' )
for node in hosts:
output( '%s -> ' % node.name )
for dest in hosts:
if node != dest:
opts = ''
if timeout:
opts = '-W %s' % timeout
if dest.intfs:
result = node.cmd( 'ping -c1 %s %s' %
(opts, dest.IP()) )
sent, received = self._parsePing( result )
else:
sent, received = 0, 0
packets += sent
if received > sent:
error( '*** Error: received too many packets' )
error( '%s' % result )
node.cmdPrint( 'route' )
exit( 1 )
lost += sent - received
output( ( '%s ' % dest.name ) if received else 'X ' )
output( '\n' )
if packets > 0:
ploss = 100.0 * lost / packets
received = packets - lost
output( "*** Results: %i%% dropped (%d/%d received)\n" %
( ploss, received, packets ) )
else:
ploss = 0
output( "*** Warning: No packets sent\n" )
return ploss
@staticmethod
def _parsePingFull( pingOutput ):
"Parse ping output and return all data."
errorTuple = (1, 0, 0, 0, 0, 0)
# Check for downed link
r = r'[uU]nreachable'
m = re.search( r, pingOutput )
if m is not None:
return errorTuple
r = r'(\d+) packets transmitted, (\d+) received'
m = re.search( r, pingOutput )
if m is None:
error( '*** Error: could not parse ping output: %s\n' %
pingOutput )
return errorTuple
sent, received = int( m.group( 1 ) ), int( m.group( 2 ) )
r = r'rtt min/avg/max/mdev = '
r += r'(\d+\.\d+)/(\d+\.\d+)/(\d+\.\d+)/(\d+\.\d+) ms'
m = re.search( r, pingOutput )
if m is None:
if received == 0:
return errorTuple
error( '*** Error: could not parse ping output: %s\n' %
pingOutput )
return errorTuple
rttmin = float( m.group( 1 ) )
rttavg = float( m.group( 2 ) )
rttmax = float( m.group( 3 ) )
rttdev = float( m.group( 4 ) )
return sent, received, rttmin, rttavg, rttmax, rttdev
def pingFull( self, hosts=None, timeout=None ):
"""Ping between all specified hosts and return all data.
hosts: list of hosts
timeout: time to wait for a response, as string
returns: all ping data; see function body."""
# should we check if running?
# Each value is a tuple: (src, dsd, [all ping outputs])
all_outputs = []
if not hosts:
hosts = self.hosts
output( '*** Ping: testing ping reachability\n' )
for node in hosts:
output( '%s -> ' % node.name )
for dest in hosts:
if node != dest:
opts = ''
if timeout:
opts = '-W %s' % timeout
result = node.cmd( 'ping -c1 %s %s' % (opts, dest.IP()) )
outputs = self._parsePingFull( result )
sent, received, rttmin, rttavg, rttmax, rttdev = outputs
all_outputs.append( (node, dest, outputs) )
output( ( '%s ' % dest.name ) if received else 'X ' )
output( '\n' )
output( "*** Results: \n" )
for outputs in all_outputs:
src, dest, ping_outputs = outputs
sent, received, rttmin, rttavg, rttmax, rttdev = ping_outputs
output( " %s->%s: %s/%s, " % (src, dest, sent, received ) )
output( "rtt min/avg/max/mdev %0.3f/%0.3f/%0.3f/%0.3f ms\n" %
(rttmin, rttavg, rttmax, rttdev) )
return all_outputs
def pingAll( self, timeout=None ):
"""Ping between all hosts.
returns: ploss packet loss percentage"""
return self.ping( timeout=timeout )
def pingPair( self ):
"""Ping between first two hosts, useful for testing.
returns: ploss packet loss percentage"""
hosts = [ self.hosts[ 0 ], self.hosts[ 1 ] ]
return self.ping( hosts=hosts )
def pingAllFull( self ):
"""Ping between all hosts.
returns: ploss packet loss percentage"""
return self.pingFull()
def pingPairFull( self ):
"""Ping between first two hosts, useful for testing.
returns: ploss packet loss percentage"""
hosts = [ self.hosts[ 0 ], self.hosts[ 1 ] ]
return self.pingFull( hosts=hosts )
@staticmethod
def _parseIperf( iperfOutput ):
"""Parse iperf output and return bandwidth.
iperfOutput: string
returns: result string"""
r = r'([\d\.]+ \w+/sec)'
m = re.findall( r, iperfOutput )
if m:
return m[-1]
else:
# was: raise Exception(...)
error( 'could not parse iperf output: ' + iperfOutput )
return ''
# XXX This should be cleaned up
def iperf( self, hosts=None, l4Type='TCP', udpBw='10M', fmt=None,
seconds=5, port=5001):
"""Run iperf between two hosts.
hosts: list of hosts; if None, uses first and last hosts
l4Type: string, one of [ TCP, UDP ]
udpBw: bandwidth target for UDP test
fmt: iperf format argument if any
seconds: iperf time to transmit
port: iperf port
returns: two-element array of [ server, client ] speeds
note: send() is buffered, so client rate can be much higher than
the actual transmission rate; on an unloaded system, server
rate should be much closer to the actual receive rate"""
hosts = hosts or [ self.hosts[ 0 ], self.hosts[ -1 ] ]
assert len( hosts ) == 2
client, server = hosts
output( '*** Iperf: testing', l4Type, 'bandwidth between',
client, 'and', server, '\n' )
server.cmd( 'killall -9 iperf' )
iperfArgs = 'iperf -p %d ' % port
bwArgs = ''
if l4Type == 'UDP':
iperfArgs += '-u '
bwArgs = '-b ' + udpBw + ' '
elif l4Type != 'TCP':
raise Exception( 'Unexpected l4 type: %s' % l4Type )
if fmt:
iperfArgs += '-f %s ' % fmt
server.sendCmd( iperfArgs + '-s' )
if l4Type == 'TCP':
if not waitListening( client, server.IP(), port ):
raise Exception( 'Could not connect to iperf on port %d'
% port )
cliout = client.cmd( iperfArgs + '-t %d -c ' % seconds +
server.IP() + ' ' + bwArgs )
debug( 'Client output: %s\n' % cliout )
server.sendInt()
servout = server.waitOutput()
debug( 'Server output: %s\n' % servout )
result = [ self._parseIperf( servout ), self._parseIperf( cliout ) ]
if l4Type == 'UDP':
result.insert( 0, udpBw )
output( '*** Results: %s\n' % result )
return result
def runCpuLimitTest( self, cpu, duration=5 ):
"""run CPU limit test with 'while true' processes.
cpu: desired CPU fraction of each host
duration: test duration in seconds (integer)
returns a single list of measured CPU fractions as floats.
"""
cores = int( quietRun( 'nproc' ) )
pct = cpu * 100
info( '*** Testing CPU %.0f%% bandwidth limit\n' % pct )
hosts = self.hosts
cores = int( quietRun( 'nproc' ) )
# number of processes to run a while loop on per host
num_procs = int( ceil( cores * cpu ) )
pids = {}
for h in hosts:
pids[ h ] = []
for _core in range( num_procs ):
h.cmd( 'while true; do a=1; done &' )
pids[ h ].append( h.cmd( 'echo $!' ).strip() )
outputs = {}
time = {}
# get the initial cpu time for each host
for host in hosts:
outputs[ host ] = []
with open( '/sys/fs/cgroup/cpuacct/%s/cpuacct.usage' %
host, 'r' ) as f:
time[ host ] = float( f.read() )
for _ in range( duration ):
sleep( 1 )
for host in hosts:
with open( '/sys/fs/cgroup/cpuacct/%s/cpuacct.usage' %
host, 'r' ) as f:
readTime = float( f.read() )
outputs[ host ].append( ( ( readTime - time[ host ] )
/ 1000000000 ) / cores * 100 )
time[ host ] = readTime
for h, pids in pids.items():
for pid in pids:
h.cmd( 'kill -9 %s' % pid )
cpu_fractions = []
for _host, outputs in outputs.items():
for pct in outputs:
cpu_fractions.append( pct )
output( '*** Results: %s\n' % cpu_fractions )
return cpu_fractions
# BL: I think this can be rewritten now that we have
# a real link class.
def configLinkStatus( self, src, dst, status ):
"""Change status of src <-> dst links.
src: node name
dst: node name
status: string {up, down}"""
if src not in self.nameToNode:
error( 'src not in network: %s\n' % src )
elif dst not in self.nameToNode:
error( 'dst not in network: %s\n' % dst )
else:
src = self.nameToNode[ src ]
dst = self.nameToNode[ dst ]
connections = src.connectionsTo( dst )
if len( connections ) == 0:
error( 'src and dst not connected: %s %s\n' % ( src, dst) )
for srcIntf, dstIntf in connections:
result = srcIntf.ifconfig( status )
if result:
error( 'link src status change failed: %s\n' % result )
result = dstIntf.ifconfig( status )
if result:
error( 'link dst status change failed: %s\n' % result )
def interact( self ):
"Start network and run our simple CLI."
self.start()
result = CLI( self )
self.stop()
return result
inited = False
@classmethod
def init( cls ):
"Initialize Mininet"
if cls.inited:
return
ensureRoot()
fixLimits()
cls.inited = True
class MininetWithControlNet( Mininet ):
"""Control network support:
Create an explicit control network. Currently this is only
used/usable with the user datapath.
Notes:
1. If the controller and switches are in the same (e.g. root)
namespace, they can just use the loopback connection.
2. If we can get unix domain sockets to work, we can use them
instead of an explicit control network.
3. Instead of routing, we could bridge or use 'in-band' control.
4. Even if we dispense with this in general, it could still be
useful for people who wish to simulate a separate control
network (since real networks may need one!)
5. Basically nobody ever used this code, so it has been moved
into its own class.
6. Ultimately we may wish to extend this to allow us to create a
control network which every node's control interface is
attached to."""
def configureControlNetwork( self ):
"Configure control network."
self.configureRoutedControlNetwork()
# We still need to figure out the right way to pass
# in the control network location.
def configureRoutedControlNetwork( self, ip='192.168.123.1',
prefixLen=16 ):
"""Configure a routed control network on controller and switches.
For use with the user datapath only right now."""
controller = self.controllers[ 0 ]
info( controller.name + ' <->' )
cip = ip
snum = ipParse( ip )
for switch in self.switches:
info( ' ' + switch.name )
link = self.link( switch, controller, port1=0 )
sintf, cintf = link.intf1, link.intf2
switch.controlIntf = sintf
snum += 1
while snum & 0xff in [ 0, 255 ]:
snum += 1
sip = ipStr( snum )
cintf.setIP( cip, prefixLen )
sintf.setIP( sip, prefixLen )
controller.setHostRoute( sip, cintf )
switch.setHostRoute( cip, sintf )
info( '\n' )
info( '*** Testing control network\n' )
while not cintf.isUp():
info( '*** Waiting for', cintf, 'to come up\n' )
sleep( 1 )
for switch in self.switches:
while not sintf.isUp():
info( '*** Waiting for', sintf, 'to come up\n' )
sleep( 1 )
if self.ping( hosts=[ switch, controller ] ) != 0:
error( '*** Error: control network test failed\n' )
exit( 1 )
info( '\n' )
0