Bug 1881213
| Summary: | Make MCO handle install-time FeatureGate, revert workaround for IPv6DualStack | ||
|---|---|---|---|
| Product: | OpenShift Container Platform | Reporter: | Dan Winship <danw> |
| Component: | Node | Assignee: | Ryan Phillips <rphillips> |
| Node sub component: | CRI-O | QA Contact: | Weinan Liu <weinliu> |
| Status: | CLOSED WONTFIX | Docs Contact: | |
| Severity: | high | ||
| Priority: | medium | CC: | achernet, aos-bugs, fpaoline, fsimonce, jokerman, kgarriso, mcornea, mnguyen, rphillips, tsweeney, umohnani |
| Version: | 4.7 | Keywords: | UpcomingSprint |
| Target Milestone: | --- | ||
| Target Release: | 4.7.0 | ||
| Hardware: | Unspecified | ||
| OS: | Unspecified | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | If docs needed, set a value | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | 1881057 | Environment: | |
| Last Closed: | 2021-01-11 14:24:48 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
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Description
Dan Winship
2020-09-21 20:02:19 UTC
https://github.com/openshift/machine-config-operator/pull/2108 adds the workaround suggested above, making MCO ignore the IPv6DualStack feature gate when generating the kubelet config, which results in the bootstrap and "real" configurations ending up the same. But (a) it's an ugly hack that should be replaced with a real solution, and (b) it won't work for 4.7 anyway, because kubelet will actually have code that depends on the IPv6DualStack feature gate in 1.20 so we'll need the gate to be enabled correctly. To reproduce just add a FeatureGate object to the install manifest directory. eg: apiVersion: config.openshift.io/v1 kind: FeatureGate metadata: name: cluster spec: featureSet: IPv6DualStackNoUpgrade well, except that that one won't trigger the bug now, but `featureSet: LatencySensitive` should work. > Assignee: amurdaca → danw
uh, this is generic MCO code, not anything networking-related. (And note that this bz is for 4.7; I implemented an IPv6DualStack-specific hack for 4.6 so that the underlying bug didn't need to be fixed right away, but the underlying bug is not related to dual-stack or anything networking-specific, it's just about how the boostrap MachineConfig is generated.)
So this would be on the Node team to implement day1 feature gate support - moving there. This should affect 4.7 only right? Would make sense to change the Version field to 4.7? My understanding is the 4.6 clone is fixed. Yeah, we can bump this up to be 4.7 only. FeatureGates are all Day 2 operations. The API server, kubelet, and controller manager need to all be synced with the allowed featuregate. Applying a FeatureGate - day 0 - is not supported [1]. [1] https://docs.openshift.com/container-platform/4.6/nodes/clusters/nodes-cluster-enabling-features.html#nodes-cluster-enabling-features-cluster_nodes-cluster-enabling If we want to support Day 0 or Day 1 FeatureGates, then there needs to be a higher level epic. (In reply to Ryan Phillips from comment #7) > FeatureGates are all Day 2 operations. The API server, kubelet, and > controller manager need to all be synced with the allowed featuregate. > Applying a FeatureGate - day 0 - is not supported [1] (The linked doc does not actually say that applying feature gates on day 0 is not supported. It's true that it doesn't document how you'd do it, but is that really the same thing?) At the moment, we don't allow changing between single- and dual-stack after install time (most networking configuration is day-0-only), so if a cluster is going to be dual stack, that has to be configured at install time, which, at the moment, means a non-default feature gate must be set at install time. It seems plausible this scenario may happen again in the future, though, at the same time, (a) we will _eventually_ support upgrading from single- to dual-stack post-install, meaning people could set the FeatureGate on day 2; and (b) dual-stack will eventually not require a non-default feature gate anyway, so the problem will just go away. And for 4.7, we already have another workaround for this problem (https://github.com/openshift/machine-config-operator/pull/2277/commits/a0c44de3) So maybe this is WONTFIX? Thanks Dan... If we want to explore featuregate enablement let's open an Epic. Since we have workarounds, I will close this bug as WONTFIX. The needinfo request[s] on this closed bug have been removed as they have been unresolved for 500 days |