Mininet/OpenFlow/POX - Connection between subnets

Question

I'm working with a Mininet topology that has this structure with 3 switches and 4 hosts:

         +--+
         |s1|
         +--+
          |
    ------+---------
    |              |
   +--+          +--+
   |s2|          |s3|
   +--+          +--+
   |  |          |  |
+--+  +--+    +--+  +--+
|h1|  |h2|    |h3|  |h4|
+--+  +--+    +--+  +--+

I'm also using POX in python to create an SDN controller for the network. And here is where my issue comes.

I'm just setting the switches like hubs to test connectivity and after that apply custom rules to the network.

Setting switches like hubs and just flooding all packets makes connectivity between hosts in the same subnet works (ie h1 can connect with h2 and h3 can connect with h4). However, I cannot make it for h1 to reach h3.

When I try to ping from one to the other it fails and prints "Destination Host Unreachable" and I cannot understand why.

For what I can see in the controller, s2 is flooding the packets but none of them are reaching s1. I've tried flooding with both of.OFPP_ALL and of.OFPP_FLOOD .

Mininet shows the links between nodes:

I really could use some help here. Either what do I need to do or where I can look it up. Because POX documentation is really bad and I can't find anything.

---

Solved

Got it. My main problem here was setting s2 and s3 to connect to s1 on port 0 (reserved for the local interface) So when I tried to access that port something went wrong.

Answer 1

也许您可以为所有主机在同一子网下分配IP地址