On 20 December 2017 at 15:52, Saku Ytti <saku@ytti.fi> wrote:
On 20 December 2017 at 16:55, Denys Fedoryshchenko <denys@visp.net.lb> wrote:
And for me, it sounds like faulty aggregation + shaping setup, for example, i heard once if i do policing on some models of Cisco switch, on an aggregated interface, if it has 4 interfaces it will install 25% policer on each interface and if hashing is done by dst ip only, i will face such issue, but that is old and cheap model, as i recall.
One such old and cheap model is ASR9k trident, typhoon and tomahawk.
It's actually pretty demanding problem, as technically two linecards or even just ports sitting on two different NPU might as well be different routers, they don't have good way to communicate to each other on BW use. So N policer being installed as N/member_count per link is very typical.
Hi, In the case of ASR9K IOS-XR 6.0.1 added the following command: "hw-module all qos-mode bundle-qos-aggregate-mode" This splits the bandwidth over the links and takes into account the link bandwidth; with bundle bandwidth 50G (with 10G+40G members) the ratios become 5/1 and 5/4 respectively (it is supporting unbalanced member link speeds). Also the NPUs don't need to talk to each other on the ASR9K; the central fabric arbiter has a view of bandwidth per VoQ and can control the bandwidth across the LAG member interfaces when they are spread over multiple lines cards and NPUs. Cheers, James,