[nox-dev] Python API buffer_id None problems
Hi developers. It seems that there is an inconsistency in python API (destiny branch) for using buffer_id. Namely, send_openflow documentation states that buffer_id -1 should be used to indicate no buffer but in the fact it tests for None. But apart from that, if you supply None to this function the call will fail with the following error: (openflow typemap) py argument to Buffer must be of type str, instead received nox.lib.packet.ethernet.ethernet instance at 0x7fbe65001b90 as far as I can tell, the problem occurs inside the call self.ctxt.send_openflow_packet_acts(dp_id, packet, oactions, inport) in the send_openflow_packet() function. Any idea what might be the problem? I can debug it even more if you tell me where to find the implementation of context. Kind regards Peter Peresini ___ nox-dev mailing list nox-dev@noxrepo.org http://noxrepo.org/mailman/listinfo/nox-dev
Re: [nox-dev] Python API buffer_id None problems
Can you please show us the code you are using to call send_openflow()? -- Murphy On Jan 17, 2012, at 1:40 AM, Peter Peresini wrote: Hi developers. It seems that there is an inconsistency in python API (destiny branch) for using buffer_id. Namely, send_openflow documentation states that buffer_id -1 should be used to indicate no buffer but in the fact it tests for None. But apart from that, if you supply None to this function the call will fail with the following error: (openflow typemap) py argument to Buffer must be of type str, instead received nox.lib.packet.ethernet.ethernet instance at 0x7fbe65001b90 as far as I can tell, the problem occurs inside the call self.ctxt.send_openflow_packet_acts(dp_id, packet, oactions, inport) in the send_openflow_packet() function. Any idea what might be the problem? I can debug it even more if you tell me where to find the implementation of context. Kind regards Peter Peresini ___ 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
Re: [nox-dev] Python API buffer_id None problems
You're right about the documentation and the implementation being mismatched. The implementation is correct, the documentation is outdated. The error you see when you pass None as the buffer ID is almost certainly in your code and not in NOX. The error message is not that clear, but it's telling you that the packet argument must be a str, and you are passing an ethernet object from the packet library. You need to either convert this to a string (packet.tostring()), or try to use the original buffer (packet.arr or packet.arr.tostring(); I can't remember). Hope that helps. -- Murphy On Jan 17, 2012, at 5:31 AM, Peter Peresini wrote: I can reproduce it with following simple command, packet is the packet received in packet_in_callback, actions is a combination of setting ToS and forwarding to a single port. self.send_openflow(datapath_id, None, packet, actions, inport=inport) Kind regards Peter On Tue, Jan 17, 2012 at 11:42 AM, Murphy McCauley jam...@nau.edu wrote: Can you please show us the code you are using to call send_openflow()? -- Murphy On Jan 17, 2012, at 1:40 AM, Peter Peresini wrote: Hi developers. It seems that there is an inconsistency in python API (destiny branch) for using buffer_id. Namely, send_openflow documentation states that buffer_id -1 should be used to indicate no buffer but in the fact it tests for None. But apart from that, if you supply None to this function the call will fail with the following error: (openflow typemap) py argument to Buffer must be of type str, instead received nox.lib.packet.ethernet.ethernet instance at 0x7fbe65001b90 as far as I can tell, the problem occurs inside the call self.ctxt.send_openflow_packet_acts(dp_id, packet, oactions, inport) in the send_openflow_packet() function. Any idea what might be the problem? I can debug it even more if you tell me where to find the implementation of context. Kind regards Peter Peresini ___ 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
Re: [nox-dev] Python API buffer_id None problems
Hi Murphy, thanks a lot, packet.arr helped. But the documentation could be improved and at least hint that packet argument is actually packet.arr Best wishes Peter On Tue, Jan 17, 2012 at 3:30 PM, Murphy McCauley jam...@nau.edu wrote: You're right about the documentation and the implementation being mismatched. The implementation is correct, the documentation is outdated. The error you see when you pass None as the buffer ID is almost certainly in your code and not in NOX. The error message is not that clear, but it's telling you that the packet argument must be a str, and you are passing an ethernet object from the packet library. You need to either convert this to a string (packet.tostring()), or try to use the original buffer (packet.arr or packet.arr.tostring(); I can't remember). Hope that helps. -- Murphy On Jan 17, 2012, at 5:31 AM, Peter Peresini wrote: I can reproduce it with following simple command, packet is the packet received in packet_in_callback, actions is a combination of setting ToS and forwarding to a single port. self.send_openflow(datapath_id, None, packet, actions, inport=inport) Kind regards Peter On Tue, Jan 17, 2012 at 11:42 AM, Murphy McCauley jam...@nau.edu wrote: Can you please show us the code you are using to call send_openflow()? -- Murphy On Jan 17, 2012, at 1:40 AM, Peter Peresini wrote: Hi developers. It seems that there is an inconsistency in python API (destiny branch) for using buffer_id. Namely, send_openflow documentation states that buffer_id -1 should be used to indicate no buffer but in the fact it tests for None. But apart from that, if you supply None to this function the call will fail with the following error: (openflow typemap) py argument to Buffer must be of type str, instead received nox.lib.packet.ethernet.ethernet instance at 0x7fbe65001b90 as far as I can tell, the problem occurs inside the call self.ctxt.send_openflow_packet_acts(dp_id, packet, oactions, inport) in the send_openflow_packet() function. Any idea what might be the problem? I can debug it even more if you tell me where to find the implementation of context. Kind regards Peter Peresini ___ 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
[nox-dev] 'Monitoring' component status
Hi all, I'm currently writing an SNMP subagent to interface with NOX to fetch openflow statistics from NOX. To this end, I was thinking of fetching the statistics via JSON messages. I noticed that netapps/monitoring in the destiny branch caches stats about connected datapaths, and it looks like it could be useful for my project. What is the current status of the monitoring component in the destiny branch? - Is the interface likely to change much? - What information does it expose? - Are there any scripts like src/scripts/nox-console.py that have examples of how to structure messages to get certain types of replies? Cheers, Joe ___ nox-dev mailing list nox-dev@noxrepo.org http://noxrepo.org/mailman/listinfo/nox-dev
[nox-dev] NOX on IRC
The nox-dev mailing list is still the best way discuss NOX or ask for help, but there is now also a IRC channel where NOX users and developers can hangout for a more real-time type of interaction. Join us on #noxcontroller on freenode servers. (For instant web-based access: http://webchat.freenode.net/ ) ___ nox-dev mailing list nox-dev@noxrepo.org http://noxrepo.org/mailman/listinfo/nox-dev
Re: [nox-dev] 'Monitoring' component status
Hi Joe, That's right, monitoring periodically queries switches for statistics and exposes that info. The interface is probably not going to chance any time soon. It has been used and tested to some extent, and has been proven ok for what it used so far. It exposes information like table_stats, port_stats, aggregate_stats I'm not aware of scripts that demonstrate its usage, but the GUI interacts with monitoring to display some switch statistics etc. So if you wanted to delve into the code there you could find an example of how to use the API. (It's probably more complicated than you need since, 'messenger' is used between the GUI and monitoring for their communication. You probably don't care about interfacing with an external program like that) On Tue, Jan 17, 2012 at 5:58 PM, Joe Stringer joestrin...@google.comwrote: Hi all, I'm currently writing an SNMP subagent to interface with NOX to fetch openflow statistics from NOX. To this end, I was thinking of fetching the statistics via JSON messages. I noticed that netapps/monitoring in the destiny branch caches stats about connected datapaths, and it looks like it could be useful for my project. What is the current status of the monitoring component in the destiny branch? - Is the interface likely to change much? - What information does it expose? - Are there any scripts like src/scripts/nox-console.py that have examples of how to structure messages to get certain types of replies? Cheers, Joe ___ 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
