Description

On the path to enabling the DeclarativeHotplugVolumes feature gate we want to deprecate ephemeral hotplug disks which will no longer be supported.

We should build on the telemetry that identifies these VMs to also raise an alert to the user and a runbook that explains how a user can switch to persistent hotplug volumes instead.

In the deprecation notice we must explain what will happen when support is removed (the disks will be unplugged during upgrade) and in which release this change will happen (likely 4.22).

Reference

• Information from CCS about deprecation notices https://spaces.redhat.com/x/CgT9Kg 
• Deprecated features are supported but will be removed in a future version. Deprecating a feature is a signal to customers that they should not use the feature for new deployments.

Formatting example

<feature> is deprecated

The <feature>, which <purpose>, is deprecated and might be removed in a future major release. You can <purpose> by using <alternative> instead.

TICKET-REFERENCE