The fundamental problem here is that there's no always-applicable way to know 
when a host leaves.

The only mechanism used in NOX now is a timeout.  You could adjust this timeout 
-- the best value for it depends on how talkative your hosts are.

You might also extend the host tracker to watch the link state, but that only 
works in some scenarios.

I have also suggested that we track hosts by periodically ARP-pinging them, 
though I don't think anyone has ever actually implemented this.

Hope that helps.

-- Murphy

On Dec 1, 2011, at 11:29 PM, 王健 wrote:

> Hi all:
>       I have a question to consult you. The NOX GUI can display a whole 
> network topology when run the command: ./nox_core -v -v -i ptcp:6633 
> monitoring discovery topology trackhost_pktin. But it cann't update timely 
> when a host leave from network, in other words, the host is still in the 
> network topology which you can see in NOX GUI. I think it may be lack of some 
> component when run the command, am i right? Which one to be used and how to 
> get it? would you like to tell me, thank you very much~
> Best Wishes
>                                                                               
>                                                      
>                                                                               
>                                                                           
> Wang Jian
>                                                                               
>                                                                    Friday, 
> December 2,2011
> 
> 
> At 2011-11-29 03:01:56,"Murphy McCauley" <jam...@nau.edu> wrote:
> I think the attachment is being scrubbed. Maybe you can send an image?
> 
> Though offhand, I don't know what I can tell you.  What do mean by 
> unreachable?  Devices connected to the netfpga switch can't ping devices 
> connected to the openwrt switch?  What NOX components are you running?
> 
> -- Murphy
> 
> On Nov 25, 2011, at 12:09 AM, 王健 wrote:
> 
>> Hi Murphy:
>>      Thank you for your last reply , your suggest is right. Recently i built 
>> a openflow network,you can see the topology in the attachment. The 
>> connection between openflow switch(netfpga) and openwrt(openflow wireless) 
>> is unreachable, i mark it in blue. What's wrong with it, would you like to 
>> give me some advice for solving this problem,thank you very much! if there 
>> is something else you want to know, please tell me.
>> Best Wishes
>>                                                                              
>>                             &n bsp;                Wang Jian
>>                                                                              
>>                                 Friday, November 25, 2011   
>>              
>> 
>> 
>> <topology v1.1.docx>
> 
> 
> 
> _______________________________________________
> nox-dev mailing list
> nox-dev@noxrepo.org
> http://noxrepo.org/mailman/listinfo/nox-dev

_______________________________________________
nox-dev mailing list
nox-dev@noxrepo.org
http://noxrepo.org/mailman/listinfo/nox-dev

Reply via email to