diff --git a/docs/community/20231016-in-place-upgrades.md b/docs/community/20231016-in-place-upgrades.md new file mode 100644 index 000000000000..e66f22e3d84f --- /dev/null +++ b/docs/community/20231016-in-place-upgrades.md @@ -0,0 +1,53 @@ +--- +title: Feature Group for In-place Upgrades support in Cluster API +authors: + - "@g-gaston" +reviewers: + - "@dharmjit" + - "@vincepri" + - "@sbueringer" + - "@fabriziopandini" +creation-date: 2023-10-16 +last-updated: 2023-10-16 +status: proposed +see-also: + - https://github.com/kubernetes-sigs/cluster-api/issues/9489 + - https://docs.google.com/document/d/1CqQ1SAqJD264PsDeMj_Z3HhZxe7DViNkpJ9d5q-2Zck +--- +# In-place upgrades Feature Group + +This document briefly outlines the scope, communication media, and stakeholders for a formal Feature Group dedicated to defining a Cluster API-approved solution to upgrade the kubernetes components running in CAPI managed nodes without replacing those machines. + +## User Story and Problem Statement + +As a CAPI Kubernetes cluster admin I want to upgrade the k8s components (for example, a minor Kubernetes upgrade) of my cluster without replacing the machines. + +At present, CAPI has "immutable infrastructure" as one of its axioms: once created, Machines are not updated, they are just replaced (a new one is created and old one is deleted). As a consequence, the only supported upgrade strategy is rolling update. However, for certain use cases (such as Single-Node Clusters with no spare capacity, Multi-Node Clusters with VM/OS customizations for high-performance/low-latency workloads or dependency on local persistent storage), upgrading a cluster via RollingUpdate strategy could either be not feasible or a costly operation (requiring to re-apply customizations on newer nodes and hence more downtime). + +## Scope + +The scope of this effort will be the following: + +1. Define the scope of what In-place upgrades means in the context of Cluster API. +2. Write a CAPI proposal with the recommended solution. + +## Communication + +We will meet on [Wednesdays at 08:00 PT (Pacific Time)][zoomMeeting]. [Convert to your timezone](https://dateful.com/time-zone-converter?t=09:00&tz=PT%20%28Pacific%20Time%29). Meeting notes will be documented in this [Google Doc](https://docs.google.com/document/d/1GmRd6MyQ0mWAoJV6rCHhZTSTtKMKHdJzhXm0BLBXOnw). + +Regular, summarized updates of group progress will be provided during weekly Cluster API office hours on Wednesdays @ 10:00 PT on [Zoom][zoomMeeting]. + +Chat with stakeholders on Kubernetes [Slack](http://slack.k8s.io/) in the [cluster-api](https://kubernetes.slack.com/archives/C8TSNPY4T) channel. + +## Stakeholders + +Primary Stakeholders are listed below: + +- Mayur Das (@mayur-tolexo, VMware) +- Alexander Demicev (@alexander-demicev, SUSE) +- Scott Dodson (@sdodson, Red Hat) +- Guillermo Gaston (@g-gaston, AWS) +- Furkat Gofurov (@furkatgofurov7, SUSE) +- Dharmjit Singh (@dharmjit, VMware) + +[zoomMeeting]: https://zoom.us/j/861487554