Clean up sshd.py and its test so it works on VirtualBox

examples/sshd.py

@@ -21,7 +21,7 @@ import sys
 from mininet.net import Mininet
 from mininet.cli import CLI
 from mininet.log import lg
-from mininet.node import Node, OVSKernelSwitch
+from mininet.node import Node
 from mininet.topolib import TreeTopo
 from mininet.link import Link
 
@@ -30,29 +30,33 @@ def TreeNet( depth=1, fanout=2, **kwargs ):
     topo = TreeTopo( depth, fanout )
     return Mininet( topo, **kwargs )
 
-def connectToRootNS( network, switch, ip, prefixLen, routes ):
+def connectToRootNS( network, switch, ip, routes ):
     """Connect hosts to root namespace via switch. Starts network.
       network: Mininet() network object
       switch: switch to connect to root namespace
       ip: IP address for root namespace node
-      prefixLen: IP address prefix length (e.g. 8, 16, 24)
       routes: host networks to route to"""
     # Create a node in root namespace and link to switch 0
     root = Node( 'root', inNamespace=False )
     intf = Link( root, switch ).intf1
-    root.setIP( ip, prefixLen, intf )
+    root.setIP( ip, intf=intf )
     # Start network that now includes link to root namespace
     network.start()
     # Add routes from root ns to hosts
     for route in routes:
         root.cmd( 'route add -net ' + route + ' dev ' + str( intf ) )
 
-def sshd( network, cmd='/usr/sbin/sshd', opts='-D' ):
+def sshd( network, cmd='/usr/sbin/sshd', opts='-D',
-    "Start a network, connect it to root ns, and run sshd on all hosts."
+          ip='10.123.123.1/32', routes=None, switch=None ):
-    switch = network.switches[ 0 ]  # switch to use
+    """Start a network, connect it to root ns, and run sshd on all hosts.
-    ip = '10.123.123.1'  # our IP address on host network
+       ip: root-eth0 IP address in root namespace (10.123.123.1/32)
-    routes = [ '10.0.0.0/8' ]  # host networks to route to
+       routes: Mininet host networks to route to (10.0/24)
-    connectToRootNS( network, switch, ip, 8, routes )
+       switch: Mininet switch to connect to root namespace (s1)"""
+    if not switch:
+        switch = network[ 's1' ]  # switch to use
+    if not routes:
+         routes = [ '10.0.0.0/24' ]
+    connectToRootNS( network, switch, ip, routes )
     for host in network.hosts:
         host.cmd( cmd + ' ' + opts + '&' )
     print
@@ -69,7 +73,9 @@ def sshd( network, cmd='/usr/sbin/sshd', opts='-D' ):
 
 if __name__ == '__main__':
     lg.setLogLevel( 'info')
-    net = TreeNet( depth=1, fanout=4, switch=OVSKernelSwitch )
+    net = TreeNet( depth=1, fanout=4 )
-    # get sshd args from the command line; default: -D
+    # get sshd args from the command line or use default args
-    opts = ' '.join( sys.argv[ 1: ] ) if len( sys.argv ) > 1 else '-D'
+    # useDNS=no -u0 to avoid reverse DNS lookup timeout
+    opts = ' '.join( sys.argv[ 1: ] ) if len( sys.argv ) > 1 else (
+        '-D -o UseDNS=no -u0' )
     sshd( net, opts=opts )

examples/test/test_sshd.py

@@ -40,7 +40,7 @@ class testSSHD( unittest.TestCase ):
         sh( 'cat /tmp/ssh/test_rsa.pub >> /tmp/ssh/authorized_keys' )
         cmd = ( 'python -m mininet.examples.sshd -D '
                 '-o AuthorizedKeysFile=/tmp/ssh/authorized_keys '
-                '-o StrictModes=no' )
+                '-o StrictModes=no -o UseDNS=no -u0' )
         # run example with custom sshd args
         self.net = pexpect.spawn( cmd )
         self.net.expect( 'mininet>' )