Hi Richard, There is a lot of part to your email. I will comment on parts that I have answers to inline.
Regards KK On 14 May 2010 12:23, Richard Mortier <[email protected]> wrote: > hi; this might not be an expected use but i thought i'd ask about it > anyway... :) apologies for the length of the mail. > > i'm trying to use nox/openflow simply as an python API to control the > networking stack on a linux box. (this may be overkill - alternate > suggestions welcome!) i believe i've got everything running > (nox_core, ofprotocol, ofdatapath), using the latest repo versions of > each (NOX 0.8.0~full~beta, ofprotocol/ofdatapath 1.0.0). i've also > got a basic python script plugged into NOX that is handling packet_in > events, installing flows on that basis, and successfully receiving and > printing flow_mod and flow_remove events. the ofdatapath component is > running against eth0,eth1,wlan0 although only eth0 is actually > connected to anything else. > > so far so good. what i'd like to do now is to cause the linux box to > start dropping packets selectively. from past messages i understand i > should be able to do this by > - returning STOP from the packet_in handler; or > - installing a flow in the datapath with a blank action (action=[]). The latter is preferred since you might have multiple packets in a flow and so having a flow entry prevent you from receiving every single packet in NOX again. > > (please correct me if i'm wrong!) > > however, in neither case are packets dropped - if i test by pinging > one of the interfaces against which ofdatapath is running then tcpdump > still shows me the ECHO request and reply; similarly if i try > connecting to a simple client/server TCP app, the handshake and data > transfer still occurs. ie., it looks like traffic still flows > unimpeded in and out of eth0. This is strange. Either method should work. For the first method, you need to make sure nox.xml is correctly configured. For the second method, check that you have a flow entry by using dpctl dump-flows. > > if i send an OFPP_FLOOD in response from the controller (as well as > setting up a suitable flow), the incoming packet is observed on the > tap0 interface as well as eth0. > > so, to my (possibly naive) questions: > > (1) is what i'm trying to do possible? (and if not, can someone explain why?) Definitely this can be done. > > (2) in the python script i believe i'm handling datapath_join and > datapath_leave events; when i "ifconfig down" one of the interfaces > managed by ofdatapath, i see ofdatapath report to the console that the > interface went down, but i don't see any event delivered to the > controller; when i "ifconfig up" the interface, i see nothing reported > anywhere. should i expect to see anything either on the console, or > at the controller? if not, is there any way that i can cause an event > to be generated at the controller when an interface goes down or up? > > (3) as i understand it, the openflow kernel module is not currently > supported in NOX 0.8/Openflow 1.0; are there plans to bring this back, > and if so, what's the timeline? use OpenvSwitch? > > happy to provide more info/context on request. > > cheers, > -- > Richard Mortier > [email protected] > > _______________________________________________ > nox-dev mailing list > [email protected] > http://noxrepo.org/mailman/listinfo/nox-dev_noxrepo.org > _______________________________________________ nox-dev mailing list [email protected] http://noxrepo.org/mailman/listinfo/nox-dev_noxrepo.org
