A small problem about remote controller when establishing topology under Mininet

Recently re-installed the system and Mininet , the use of mininet encountered a small problem, a start to ignore the details, so that they have been troubled by this problem for a while, fortunately, later still found the problem, so record down.

$ sudo mn--topo single,3--mac--switch Ovsk--controller Remote

The above command is a common command that tells Mininet to create a topology that is connected to 1 Openvswitch by 3 hosts , setting the MAC address of each host equal to its IP, and point to a remote controller.

$./pox/pox.py Forwarding.hub

Launch the pox controller 's own hub function

If you are familiar with pox, you can see that although the hub has been running, but the controller is not successfully connected to the switch, at this time we try to enter the Pingall command in mininet, it is naturally not ping.

Looking back at the two operations that we've done, we need to note that when you create a topology, The remote controller that points to is not connected to the 127.0.0.1:6653 and 127.0.0.1:6633 (the controller has not yet started), and eventually points to the former (that is, the port number is 6653); however, our Pox controller is working on localhost by default (i.e. 127.0.0.1:6633), so the two port numbers are inconsistent, and the switch and controller cannot be connected naturally.

After you find the problem, you can specify that the remote controller works on localhost when you start mininet.

$ sudo mn--topo single,3--mac--switch Ovsk--controller remote, ip=127.0.0.1,port=6633

To start the Pox Controller hub feature

At this point, we can see the connected typeface, indicating that the controller and switch are connected, and that the switch's data path identifier (DPID) is 00-00-00-00-00-01. Then we carry on the Pingall test, the network 3 hosts each other can ping through.

Summary: The above problems are actually very small, and the use of mininet experience, it is not easy to make such a mistake; the key is to pay attention to the details, to ask yourself, what is the default configuration of the tool? Is it consistent with my current reality? It is recommended that you manually configure the tool options to suit your requirements, so that you are clear and easy to understand, and also note the hints given by the tool.

A small problem about remote controller when establishing topology under Mininet