Added INSTALL file incorporating Brandon's suggestions.

More tweaks for examples, which are still in progress.

INSTALL

@@ -0,0 +1,68 @@
+Preliminary Installation Notes
+
+- A functional netns binary is required to run mininet, but currently you
+  have to compile it and install it yourself from the included .c file:
+
+  to make it: make netns (or cc -o netns netns.c)
+  to test it: ./netns /bin/echo 
+  to 'install' a link to it:
+    sudo ln -s /home/openflow/mininet/netns /usr/local/bin/netns
+
+  Installation is simplest with a distribution that includes a kernel
+  which supports the CLONE_NETNS unshare flag by default. Debian 5.0+
+  does; Ubuntu doesn't. If your kernel doesn't support it, you will need
+  to build and install a kernel that does!
+
+- To run the iPerf test, you need to install iperf:
+
+    sudo aptitude/yum install iperf
+
+  We assume you already have ping installed.
+  
+- You may need other packages to run the examples, e.g.
+
+    sudo aptitude/yum install sshd xterm screen
+    
+  Consult the appropriate example file for details.
+  
+- To switch to the most recent OpenFlow 0.8.9 release branch (the most
+  recent one with NOX support):
+
+  git checkout -b release/0.8.9 remotes/origin/release/0.8.9
+
+  If you want to automatically load the kernel modules required
+  for OpenFlow, you could add something like the following to
+  /etc/rc.local:
+
+    insmod /home/openflow/openflow/datapath/linux-2.6/ofdatapath.ko 
+    modprobe tun
+
+- For scalable configurations, you might need to increase some of your
+  kernel limits. For example, you could add something like the following
+  to /etc/sysctl.conf (modified as necessary for your desired 
+  configuration):
+
+    # OpenFlow: get rid of ipv6
+    net.ipv6.conf.all.disable_ipv6 = 1
+    net.ipv6.conf.default.disable_ipv6 = 1
+
+    # Mininet: Increase open file limit
+    fs.file-max = 100000
+
+    # Mininet: increase network buffer space
+    net.core.wmem_max = 16777216
+    net.core.rmem_max = 16777216
+    net.ipv4.tcp_rmem = 10240 87380 16777216
+    net.ipv4.tcp_rmem = 10240 87380 16777216
+    net.core.netdev_max_backlog = 5000
+
+    # Mininet: increase arp cache size
+    net.ipv4.neigh.default.gc_thresh1 = 4096 
+    net.ipv4.neigh.default.gc_thresh2 = 8192 
+    net.ipv4.neigh.default.gc_thresh3 = 16384
+
+    # Mininet: increase routing table size
+    net.ipv4.route.max_size=32768
+
+
+

examples/linearBandwidth.py

@@ -1,10 +1,10 @@
 #!/usr/bin/python
 
 """
-Test bandwidth on a linear network of varying size, using both
+Test bandwidth on linear networks of varying size, using both
 the kernel and user datapaths.
 
-The network looks like:
+Each network looks like:
 
 h0 <-> s0 <-> s1 .. sN <-> h1
 """

examples/sshd.py

@@ -1,6 +1,13 @@
 #!/usr/bin/python
 
-"Create a network and start sshd on the hosts."
+"""Create a network and start sshd(8) on the hosts.
+   This is probably overkill - rshd(8) would be
+   perfectly adequate, considering that the openflow
+   network is private to the machine it's running on.
+   It would also be lighter weight/faster.
+   Nonetheless, most people already have sshd installed,
+   and it's a good demo to show that mininet makes a
+   'real', usable network! """
 
 from mininet import init, Node, createLink, TreeNet, Cli
 
@@ -14,8 +21,7 @@ def nets( hosts ):
    return nets.keys()
    
 def addRoutes( node, nets, intf ):
-   """Add routes from node to nets through intf, assuming
-      a 24-bit netmask."""
+   "Add routes from node to nets through intf."
    for net in nets:
       node.cmdPrint( 'route add -net ' + net + ' dev ' + intf )
 

examples/treeInteract.py

@@ -1,14 +1,10 @@
 #!/usr/bin/python
 
-"""Create a tree network and run the CLI on it."""
+"Create a tree network and run the CLI on it."
 
 from mininet import init, TreeNet, Cli
 
-def treeInteract():
-   network = TreeNet( depth=2, fanout=4, kernel=True )
-   network.run( Cli )
-      
 if __name__ == '__main__':
    init()
-   treeInteract()
-
+   network = TreeNet( depth=2, fanout=4, kernel=True )
+   network.run( Cli )

examples/xterms.py

@@ -1,6 +1,9 @@
 #!/usr/bin/python
 
-"Create a network and run an xterm (connected via screen) on each host."
+"""
+Create a network and run an xterm (connected via screen(1) ) on each host.
+Requires xterm(1) and GNU screen(1).
+"""
 
 import os
 from subprocess import Popen
@@ -16,6 +19,12 @@ def makeXterm( node, title ):
    cmd += [ '-e', 'screen', '-D', '-RR', '-S', node.name ]
    return Popen( cmd )
 
+def cleanUpScreens():
+   "Remove moldy old screen sessions."
+   # XXX We need to implement this - otherwise those darned
+   # screen sessions will just accumulate
+   pass
+   
 def makeXterms( nodes, title ):
    terms = []
    for node in nodes:
@@ -28,15 +37,14 @@ def xterms( controllers, switches, hosts ):
    terms += makeXterms( controllers, 'controller' )
    terms += makeXterms( switches, 'switch' )
    terms += makeXterms( hosts, 'host' )
-   # Wait for completion
+   # Wait for xterms to exit
    for term in terms:
       os.waitpid( term.pid, 0 )
    
-def treeXterms():
-   print "Running xterms on", os.environ[ 'DISPLAY' ]
-   network = TreeNet( depth=2, fanout=2, kernel=True )
-   network.run( xterms )
-      
 if __name__ == '__main__':
    init()
-   treeXterms()
+   print "Running xterms on", os.environ[ 'DISPLAY' ]
+   cleanUpScreens()
+   network = TreeNet( depth=2, fanout=2, kernel=True )
+   network.run( xterms )
+   cleanUpScreens()