[pox-dev] Does POX supports loops in the topology??

2013-09-11 Thread Dharani Kunnuru 
Hello Everyone,

I want to use POX controller to distributed control plane ( Logically
centralized but physically distributed) . And the topology iam going to use
should support loops? So, I want to know whether POX supports loops or not?

I have tried with single controller, All hosts are not able to communicate
with each. I have read one post in this group

http://lists.noxrepo.org/pipermail/pox-dev-noxrepo.org/2013-July/000834.html

They mention some changes to switch to allow loops? So is it possible to
configure switch to allow loops??

Please some one reply me..

-- 
*K Dharani*

Re: [pox-dev] Does POX supports loops in the topology??

2013-09-11 Thread Murphy McCauley 
Most (or all?) of the forwarding components POX ships with will cause 
broadcast/flood storms when used on topologies with loops by themselves.  This 
isn't a property of POX, but of the specific forwarding components.  It can be 
resolved in multiple ways.  One way is to disable flooding on some switch ports 
such that the flood-enabled ports form a spanning tree.  The 
openflow.spanning_tree POX component implements this method in a way which is 
at least partially agnostic to the forwarding component.

So the short answer is yes.  If you, for example, run l2_learning and 
openflow.spanning_tree (the latter of which also requires openflow.discovery, 
if I recall correctly), forwarding should work even on topologies with loops.  
See the POX manual wiki and probably the openflow.spanning_tree docstring for 
more on this.

-- Murphy

On Sep 11, 2013, at 11:02 AM, Dharani Kunnuru kunnurudhar...@gmail.com wrote:

 Hello Everyone,
 
 I want to use POX controller to distributed control plane ( Logically 
 centralized but physically distributed) . And the topology iam going to use 
 should support loops? So, I want to know whether POX supports loops or not?
 
 I have tried with single controller, All hosts are not able to communicate 
 with each. I have read one post in this group
 
 http://lists.noxrepo.org/pipermail/pox-dev-noxrepo.org/2013-July/000834.html
 
 They mention some changes to switch to allow loops? So is it possible to 
 configure switch to allow loops?? 
 
 Please some one reply me..
 
 -- 
 K Dharani

Re: [pox-dev] loop at topology problem with host_tracker

2013-09-11 Thread Murphy McCauley 
This very likely has nothing to do with host_tracker at all and the real 
problem is that you are running a forwarding component that's not prepared to 
deal with loops.

See the other pox-dev thread from today involving loops, and/or check out the 
loop question in the FAQ.

-- Murphy

On Sep 11, 2013, at 11:50 AM, adria sole adrias...@gmail.com wrote:

 Hi all,
 
 I have seen that in a topology where there are loops when I connect a host to 
 a router I get flooded of Possible duplicate host... Is this fixed in any 
 version of host_tracker.py?
 
 Thank you in advance