Unclear details around Nodes and `NetworkUnavailable: false`

[jayunit100]

It appears https://kubernetes.io/docs/concepts/architecture/nodes/#condition (sorry i meant https://kubernetes.io/docs/reference/node/node-status/#condition)

is missing any mention of how the NetworkUnavailable condition = false should be interpretted.

IF this is an "official" API that we rely on then i think its ok to rely on it in the e2e tests. but if its not an officially supported standard, i think the e2e tests shouldnt force this field to be set to "False" in order to run.

i.e.

networkReady := isConditionUnset(&node, v1.NodeNetworkUnavailable) || IsConditionSetAsExpected(&node, v1.NodeNetworkUnavailable, false)

is relying on the definition of NodeNetworkUnavialable:false to mean something like "This node should not be thought of as , in any way , testable / usable for running pods".

However, this condition is just a vanity metric. You can easily have a node that does run pods, which simply doesnt have this attached metadata, and as a metric, its managed by third party libraries / cnis /etc... so K8s itself i dont think should really rely on it... unless we document it as w/ a strict definition.

Feel free to close if im just missing the docs and theres a better place to look this up . I do see its in the v1.Types ... but i think at the very least, we need it documented on https://kubernetes.io/docs/concepts/architecture/nodes/#condition if were going to keep relying on it.

[sftim]

I think the page to fix is https://kubernetes.io/docs/reference/node/node-status/#condition

All https://k8s.io/docs/concepts/architecture/nodes/#node-status needs to do is clearly signpost people to the reference page.

[sftim]

/sig node network

[sftim]

/language en

[jayunit100]

yeah agree that page would be a good place to do it, but ...

we also need to disambiguate

• the different types of things that may toggle the value of this setting to since its so far out of bounds of what k/k/core does
• what "network configured correctly" even means... ie. to me "correctly" is "can launch pods" but to someone else, this might be "can launch pods and support network policies on them" and maybe, to others, this might be something related to security or bandwidth or ......

[jayunit100]

xref https://github.com/kubernetes/kubernetes/issues/120486 bc its a broader issue of disambiguation, talked w @aojea

[sftim]

/retitle Unclear details around Nodes and NetworkUnavailable: false

[sftim]

/triage accepted

[letmerecall]

/assign