KEP-2433: Removing traffic policy interoperability as beta graduation requirement

[robscott]

• One-line PR description: Removes traffic policy interoperability as beta graduation requirement

• Issue link: Topology Aware Routing #2433

The interoperability between InternalTrafficPolicy, ExternalTrafficPolicy, and Topology are actively being worked on by @danwinship (thanks!!). I think this is an important thing to get right, but I'm not sure it needs to block beta graduation. I expect the vast majority of users will want to user at most one of these features per Service. Open to other input here. This may all be a non-issue if all the kube-proxy updates and fixes manage to make it into 1.23, but I just wanted to start this conversation a bit earlier in case they don't.

/sig network
/cc @aojea @danwinship
/assign @thockin

[thockin]

I don't understand "the vast majority of users will want to user at most one of these features per Service". Once beta, isn't topology on by default?


[robscott]

I don't understand "the vast majority of users will want to user at most one of these features per Service". Once beta, isn't topology on by default?

Clarified on Slack but also responding here.

Beta just means the opt-in annotation is available by default, not that it is on for all services by default. I don’t think it will be very common for users to want to combine InternalTrafficPolicy and Topology on the same Service. With the current logic, if that is configured, traffic policy wins and topology hints are ignored. There is an argument that ExternalTrafficPolicy=Local + Topology for internal traffic could be useful, but I’m not sure that’s sufficient to block this graduating.

[thockin]

This makes me uncomfortable (seems mildly surprising) but I think topology feedback is really useful.

/lgtm
/approve

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