Re: [ovs-discuss] BFD with 'option : remote_ip = flow'
-Original Message- From: Raymond Burkholder [mailto:r...@oneunified.net] Sent: Wednesday, August 16, 2017 5:05 PM To: Vivek Srivastava V Cc: ovs-discuss@openvswitch.org Subject: Re: [ovs-discuss] BFD with 'option : remote_ip = flow' > On 16 Aug 2017, at 07:54, Vivek Srivastava V > wrote: > > No. I hadn't heard of multi-hop BFD before, so I looked around a bit and > found RFC 5883. That RFC, though, doesn't really provide a specification for > how to do this. Is there a detailed specification somewhere else? > > [Viveks] Unfortunately I also couldn't find any implementation > specific details about multihop BFD, other than RFC 5883 and some > configuration related info available on the net. What I could gather > is that it is mostly same as onehop BFD, with some additional > considerations- Out of curiosity, would you be able to explain what your use case is? I gather you don’t have a BFD partner on the ‘other end’ of the layer 2 link? And that you are going across some sort of layer 3 network? And if that is a multi-hop l3 network, don’t things get a bit dicey in terms of time-outs, possible changes in packet flows, etc? [Viveks] the use case is to monitor availability of DCGWs from computes in a DC with L3 fabric. There will be multiple (but limited) l3 hops in between. I believe BFD is still applicable in this scenario and it should be okay with possible change in packet flows/paths. Time-outs/false failure detections can be avoided with appropriate/tuned monitoring intervals. Do you see any other issues in this scenario? -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ___ discuss mailing list disc...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
Re: [ovs-discuss] BFD with 'option : remote_ip = flow'
> On 16 Aug 2017, at 07:54, Vivek Srivastava V > wrote: > > No. I hadn't heard of multi-hop BFD before, so I looked around a bit and > found RFC 5883. That RFC, though, doesn't really provide a specification for > how to do this. Is there a detailed specification somewhere else? > > [Viveks] Unfortunately I also couldn't find any implementation specific > details about multihop BFD, other than RFC 5883 and some configuration > related info available on the net. What I could gather is that it is mostly > same as onehop BFD, with some additional considerations- Out of curiosity, would you be able to explain what your use case is? I gather you don’t have a BFD partner on the ‘other end’ of the layer 2 link? And that you are going across some sort of layer 3 network? And if that is a multi-hop l3 network, don’t things get a bit dicey in terms of time-outs, possible changes in packet flows, etc? -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ___ discuss mailing list disc...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
Re: [ovs-discuss] BFD with 'option : remote_ip = flow'
Hi Ben, Thanks for your response. Please see below inline. Regards, Vivek -Original Message- From: Ben Pfaff [mailto:b...@ovn.org] Sent: Friday, August 11, 2017 9:24 PM To: Vivek Srivastava V Cc: ovs-discuss@openvswitch.org Subject: Re: [ovs-discuss] BFD with 'option : remote_ip = flow' On Fri, Aug 11, 2017 at 08:48:20AM +, Vivek Srivastava V wrote: > 1. Is there any way to configure/manage BFD sessions to destinations, > independent of the tunnel port/interface created? Not currently. If you have a good idea for how to extend the OVS BFD support to be more flexible, we'd accept patches. [Viveks] We are planning to create a separate table/schema for maintaining independent BFD sessions. An entry in this BFD table can be identified by a session ID generated/configured and will have same columns as we have for BFD in interface table. In future we can choose to remove the BFD related fields from interface table and use a reference (session_id) from the BFD table. WDYT? > 2. Does OVS support multi-hop BFD? In roadmap? No. I hadn't heard of multi-hop BFD before, so I looked around a bit and found RFC 5883. That RFC, though, doesn't really provide a specification for how to do this. Is there a detailed specification somewhere else? [Viveks] Unfortunately I also couldn't find any implementation specific details about multihop BFD, other than RFC 5883 and some configuration related info available on the net. What I could gather is that it is mostly same as onehop BFD, with some additional considerations- 1. uses different UDP destination port 4784 (MUST) 2. suggests session authentication (SHOULD) 3. De-multiplexing (applicable only in case of multiple BFD sessions between same pair of TEPs) So I think we should be good with supporting the first item initially. ___ discuss mailing list disc...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
Re: [ovs-discuss] BFD with 'option : remote_ip = flow'
On Fri, Aug 11, 2017 at 08:48:20AM +, Vivek Srivastava V wrote: > 1. Is there any way to configure/manage BFD sessions to destinations, > independent of the tunnel port/interface created? Not currently. If you have a good idea for how to extend the OVS BFD support to be more flexible, we'd accept patches. > 2. Does OVS support multi-hop BFD? In roadmap? No. I hadn't heard of multi-hop BFD before, so I looked around a bit and found RFC 5883. That RFC, though, doesn't really provide a specification for how to do this. Is there a detailed specification somewhere else? ___ discuss mailing list disc...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
[ovs-discuss] BFD with 'option : remote_ip = flow'
Hi, We are creating VxLAN tunnel port/interface in OVS with option : remote_ip = flow and the tunnel remote_ip is set using openflow rules. This works well, however with this option we cannot use the BFD monitoring for multiple remote TEPs, with BFD config/status interface available in interface table (as we have only one tunnel interface in this case). So I have following questions - 1. Is there any way to configure/manage BFD sessions to destinations, independent of the tunnel port/interface created? 2. Does OVS support multi-hop BFD? In roadmap? Regards, Vivek ___ discuss mailing list disc...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
