Thanks Thomas, Before we write code, let’s agree on architecture, there are always tradeoffs, pros/cons analysis on such an important topic would be in place Could someone please update me wrt SRv6 (SRH) - what’s supported/what’s planned? Thanks! Cheers, Jeff
On Mar 21, 2017, at 02:47, Thomas Morin <thomas.morin@orange.com> wrote:
Hi Jeff,
2017-03-20, Jeff Tantsura:
I think it is a requirement to have something efficient to trigger a lookup in any {routing table, vrf interface, netns}.
I hadn't tried (because no need). I thought we might achieve something like that by forwarding the packet on 'lo', or on a vrf interface, or on a veth device: wouldn't this kind of next hop specification trigger a re-enter of the packet in the IP stack after the pop operation ?
[jeff] would’t this be a tad inefficient? :)
Well, I was not implying that the above would be efficient, and I would actually have the same concern as you have. But to be honest I also lack hard facts to back this concern: e.g. I don't know whether going through a vrf interface is a small or high cost.
Best,
-Thomas
On Thu, Mar 16, 2017 at 10:45 AM, Jeff Tantsura <jefftant@gmail.com <mailto:jefftant@gmail.com>> wrote: Donald,
Wrt PHP, this is incorrect, PHP node MUST not perform IP lookup, or in fact any lookup after POP. In most cases (labeled services, L2/L3 VPN) there's another label(s) in the stack, looking it up would be fatal.
Regards, Jeff
On Mar 15, 2017, at 08:05, Donald Sharp <sharpd@cumulusnetworks.com <mailto:sharpd@cumulusnetworks.com>> wrote:
David/Roopa -
Olivier asked me about these two issues yesterday in the FRR Technical Meeting. I just wanted to make sure I didn't loose track of these questions that he had:
1) More than 2 labels in the kernel at a time, when will this be allowed in the kernel?
-> David is currently working on this issue. When he is done it will be upstreamed. So soonish(tm).
2) PenUltimate Hop Popping:
I know this issue is not trivial to solve. In fact, once the POP instruction perform, the packet must re-enter in the IP packet processing to determine what action must apply. A possible solution would be to process this packet as a new incoming IP packet when output interface is the loopback disregarding the IP address value. But, this issue is less urgent than the first one. Our OSPF Segment Routing implementation could announce if the router works in PenUltimate Hop Poping mode or not. So, for the moment, the option is force to yes.
thanks!
donald
_______________________________________________ frr mailing list frr@lists.nox.tf <mailto:frr@lists.nox.tf> https://lists.nox.tf/listinfo/frr <https://lists.nox.tf/listinfo/frr>
_______________________________________________ frr mailing list frr@lists.nox.tf <mailto:frr@lists.nox.tf> https://lists.nox.tf/listinfo/frr <https://lists.nox.tf/listinfo/frr>
_______________________________________________ frr mailing list frr@lists.nox.tf <mailto:frr%40lists.nox.tf> https://lists.nox.tf/listinfo/frr <https://lists.nox.tf/listinfo/frr>