nanog mailing list archives
Re: Lossy cogent p2p experiences?
From: Dave Cohen <craetdave () gmail com>
Date: Sat, 9 Sep 2023 16:29:49 -0400
At a previous $dayjob at a Tier 1, we would only support LAG for a customer L2/3 service if the ports were on the same card. The response we gave if customers pushed back was "we don't consider LAG a form of circuit protection, so we're not going to consider physical resiliency in the design", which was true, because we didn't, but it was beside the point. The real reason was that getting our switching/routing platform to actually run traffic symmetrically across a LAG, which most end users considered expected behavior in a LAG, required a reconfiguration of the default hash, which effectively meant that [switching/routing vendor]'s TAC wouldn't help when something invariably went wrong. So it wasn't that it wouldn't work (my recollection at least is that everything ran fine in lab environments) but we didn't trust the hardware vendor support. On Sat, Sep 9, 2023 at 3:36 PM Mark Tinka <mark@tinka.africa> wrote:
On 9/9/23 20:44, Randy Bush wrote:i am going to be foolish and comment, as i have not seen this raised if i am running a lag, i can not resist adding a bit of resilience by having it spread across line cards. surprise! line cards from vendor <any> do not have uniform hashing or rotating algorithms.We spread all our LAG's across multiple line cards wherever possible (wherever possible = chassis-based hardware). I am not intimately aware of any hashing concerns for LAG's that traverse multiple line cards in the same chassis. Mark.
-- - Dave Cohen craetdave () gmail com @dCoSays www.venicesunlight.com
Current thread:
- Re: Lossy cogent p2p experiences?, (continued)
- Re: Lossy cogent p2p experiences? Fred Baker (Sep 08)
- Re: Lossy cogent p2p experiences? Masataka Ohta (Sep 07)
- Re: Lossy cogent p2p experiences? Benny Lyne Amorsen (Sep 07)
- Re: Lossy cogent p2p experiences? Saku Ytti (Sep 07)
- Re: Lossy cogent p2p experiences? Masataka Ohta (Sep 07)
- Re: Lossy cogent p2p experiences? Mark Tinka (Sep 07)
- Re: Lossy cogent p2p experiences? Saku Ytti (Sep 07)
- Re: Lossy cogent p2p experiences? Benny Lyne Amorsen (Sep 09)
- Re: Lossy cogent p2p experiences? Randy Bush (Sep 09)
- Re: Lossy cogent p2p experiences? Mark Tinka (Sep 09)
- Re: Lossy cogent p2p experiences? Dave Cohen (Sep 09)
- Re: Lossy cogent p2p experiences? Mark Tinka (Sep 09)
- Re: Lossy cogent p2p experiences? Saku Ytti (Sep 10)
- Re: Lossy cogent p2p experiences? Mark Tinka (Sep 06)
- Re: Lossy cogent p2p experiences? Mark Tinka (Sep 06)
- Re: Lossy cogent p2p experiences? Masataka Ohta (Sep 06)
- Re: Lossy cogent p2p experiences? Nick Hilliard (Sep 03)
- Re: Lossy cogent p2p experiences? Masataka Ohta (Sep 03)
- Re: Lossy cogent p2p experiences? Nick Hilliard (Sep 03)
- Re: Lossy cogent p2p experiences? Masataka Ohta (Sep 03)
- Re: Lossy cogent p2p experiences? Nick Hilliard (Sep 02)