Known Issues with OpenShift 4.12 to 4.13 or 4.13 to 4.14 vSphere CSI Storage Migration
Historically, Kubernetes storage drivers have been delivered as “in-tree” plugins where the drivers lived and were shipped as part of the Kubernetes core code. Over the past few years, the in-tree approach has transitioned to a new standard called Container Storage Interface (CSI) where the driver’s code lives outside of Kubernetes. As a result the in-tree drivers are progressively being deprecated upstream and will be ultimately removed, and Red Hat OpenShift Container Platform is also making this transition. In order to provide a transition path to clusters that are currently using in-tree persistent volumes (PVs), a CSI migration path is offered. This process is transparent to end-users and applications (in most situations - vsphere drivers being the exception), the volumes still appear to be in-tree but the internal calls are transparently translated to CSI.
CSI migration is automatically enabled when GA, it does not require any administrator action, the process is completely transparent to both administrators and end-users. Upgraded clusters will have CSI migration automatically enabled after they upgrade to a version that supports migration. This is true for all drivers except vSphere, where we had to take a particular and unique approach on how we address the CSI migration. Please see the, Manually enabling CSI automatic migration documenation for more infomration on how to execute the vSphere CSI Storage Migration.
- Note: With OCP 4.14 the vSphere migration happens automatically. You are strongly recommended to update to at least vSphere 7.0 Update 3L or 8.0 Update 2 before upgrading to OpenShift 4.14, to avoid the currently known issues.
As is denoted, in the documentation there are some known issue that arise from possible operational situations that can cause the migration to fail; and manual interventions to need to be taken. This page denotes these issues; and where possible lists what actions you should take to correct them.
If you want to verify if you are using in-tree or csi drivers please refer to KCS 6995590 for more verification steps.