It looks like you're never actually calling your send_flow_stats_request()
method. I'd suggest you add a timer (with post_callback()) to actually invoke
send_flow_stats_request() periodically.
Also, since you've got your own code for sending requests and answering
replies, I'm not sure why you're referencing the monitoring component -- I'd
remove all mention of it from your application (because without looking back at
the code, I can't remember for sure that it doesn't eat the stats events or
something else that would get in your way).
-- Murphy
On Apr 7, 2013, at 3:31 PM, udita gangwal wrote:
> Yea, did that. and that error is no more showing up. There is no error now,
> but still I do not get any stats reply from the switch, I have no idea why.
> Do you see some error in the code? I guess the stats_request itself isn't
> going till the switch, but dont know why.
>
> The modified code is now:
>
> from nox.lib.core import *
> import nox.lib.pyopenflow as of
> from nox.netapps.monitoring.monitoring import Monitoring
> from twisted.python import log
> import logging
>
> log = logging.getLogger('nox.coreapps.examples.mymonitor')
>
> #global mymonitor instance
> #inst=None
>
>
>
>
> #for handling the flow stats in
> def flow_stats_in_handler(dpid, flows, more, xid):
> print "---------Flow stats report----------"
> print str(dpid)+" "+str(flows)
> for i in flows:
> print flows[i]
>
>
>
> class MyMonitor(Component):
>
> def __init__(self, ctxt):
> #global inst
> Component.__init__(self, ctxt)
> self.ctxt = ctxt
> log.info("Reached the first chkpoint.")
> self.Monitoring =
> ctxt.resolve("nox.netapps.monitoring.monitoring.Monitoring")
> log.info("I have come till second chkpoint")
>
> def install(self):
> log.info("inside install")
> self.register_for_flow_stats_in(flow_stats_in_handler)
>
> def getInterface(self):
> log.info("inside interface")
> return str(MyMonitor)
>
> #for sending flow stats request
> def send_flow_stats_request():
> global xid
> flows = of.ofp_match()
> flows.wildcards = of.OFPFW_ALL
> self.Monitoring.send_flow_stats_request(dpid, flows, 0xff, xid)
> xid += 1
>
>
>
>
> def getFactory():
> class Factory:
> def instance(self, ctxt):
> return MyMonitor(ctxt)
>
> return Factory()
>
>
>
>
>
>
> On Sun, Apr 7, 2013 at 11:16 PM, Murphy McCauley <[email protected]>
> wrote:
> Try adding a getInterface method to your component. Something like:
> def getInterface (self):
> return str(type(self))
>
> -- Murphy
>
> On Apr 7, 2013, at 12:49 PM, udita gangwal wrote:
>
>> Hello All,
>>
>> I have wriiten a module to obtain the individual flow entries from the OVS.
>> I run it along with the monitoring component.
>>
>> The code in the module is as follows:
>>
>> from nox.lib.core import *
>> import nox.lib.pyopenflow as of
>> from nox.netapps.monitoring.monitoring import Monitoring
>> from twisted.python import log
>> import logging
>>
>> log = logging.getLogger('nox.coreapps.examples.mymonitor')
>>
>> #global mymonitor instance
>> #inst=None
>>
>> class MyMonitor(Component):
>>
>> def __init__(self, ctxt):
>> #global inst
>> Component.__init__(self, ctxt)
>> self.ctxt = ctxt
>> log.info("Reached the first chkpoint.")
>> self.Monitoring =
>> ctxt.resolve("nox.netapps.monitoring.monitoring.Monitoring")
>> log.info("I have come till second chkpoint")
>>
>> def install(self):
>> self.register_for_flow_stats_in(flow_stats_in_handler)
>>
>>
>> #for sending flow stats request
>> def send_flow_stats_request():
>> global xid
>> flows = of.ofp_match()
>> flows.wildcards = of.OFPFW_ALL
>> self.Monitoring.send_flow_stats_request(dpid, flows, 0xff, xid)
>> xid += 1
>>
>>
>> #for handling the flow stats in
>> def flow_stats_in_handler(dpid, flows, more, xid):
>> print "---------Flow stats report----------"
>> print str(dpid)+" "+str(flows)
>> for i in flows:
>> print flows[i]
>>
>>
>> def getFactory():
>> class Factory:
>> def instance(self, ctxt):
>> return MyMonitor(ctxt)
>>
>> return Factory()
>>
>>
>>
>>
>> I run it from the command line as follows:
>>
>> sudo ./nox_core -v -i ptcp:6633 pyswitch monitoring mymonitor
>>
>>
>>
>> And I get the following error on running it:
>>
>> 00001|nox|INFO:Starting nox_core
>> (/home/openflow/noxcore/build/src/.libs/lt-nox_core)
>> 00002|monitoring|INFO:Simple monitoring started!
>> 00003|monitoring|INFO:Finished configuring monitoring
>> 00004|nox.coreapps.examples.mymonitor|INFO:Reached the first chkpoint.
>> 00005|nox.coreapps.examples.mymonitor|INFO:I have come till second chkpoint
>> 00006|nox|ERR:Cannot change the state of 'mymonitor' to INSTALLED:
>> 'mymonitor' ran into an error:
>> cannot retrieve the Python component interface description:
>>
>>
>> I have also the added the folowing entry in the meta.json file present in
>> the coreapps/example directory:
>>
>> {
>> "name": "mymonitor" ,
>> "dependencies": [
>> "python"
>> ],
>> "python": "nox.coreapps.examples.mymonitor"
>> },
>>
>> Has something else be added here?
>>
>>
>> Can someone please tell me what this error is and what has to be done to
>> solve it?
>>
>> Many Thanks,
>> Udita
>>
>>
>> On Sat, Apr 6, 2013 at 9:24 PM, Murphy McCauley <[email protected]>
>> wrote:
>> On Apr 6, 2013, at 11:13 AM, udita gangwal wrote:
>>
>> > I want to obtain the individual flow entries from the OVS and display them
>> > on the NOX console. How can I do this?
>>
>> By sending a flow_stats request and handling the response.
>>
>> > What does the monitor module do in NOX?
>>
>> It's described (briefly) on the NOX wiki:
>> https://github.com/noxrepo/nox-classic/wiki/Monitoring
>>
>> It periodically sends stats requests. You can probably either use it or
>> base your own flow stats query code on it.
>>
>> -- Murphy
>>
>
>
