Hi Angie, The feature looks great that we can now upgrade the k8s cluster at runtime. Regarding the details, I and other folks have several questions that we didn't find clues in the doc. Could you please give us the info from designer's view? * Why the upgrade complete cmd line needed? Any essential checks? * If the first master node upgrade completed on the active controller, that means the active control plane is upgraded to the new version. Then how to ensure the compatibility between upgraded controller plane and un-upgraded kubelet before step 12? * What will happen if some nodes restart unexpectedly between step 11 and 12? * How to deal with the certificates and keys of Kubernetes during upgrading? * Is upgrade rollback supported regardless the upgrade completion? * Is kubelet/kubectl patch marked as in-service patch or reboot-required patch? * Why lock/unlock is needed to upgrade kubelet? Is there a way to avoid that? Since this will impact the running pods on all nodes. Thanks, Mingyuan From: Wang, Jing (Angie) <Angie.Wang@windriver.com> Sent: Thursday, February 27, 2020 23:17 To: starlingx-discuss@lists.starlingx.io Cc: Dale, Kristal <kristal.dale@intel.com> Subject: [Starlingx-discuss] [docs]Provide doc input for 2006781 Hi All, The attached file is the documentation changes required for the story "Kubernetes upgrade support in StarlingX" (https://storyboard.openstack.org/#!/story/2006781). Thanks, Angie