Feature Overview (aka. Goal Summary)  

Allow LVMS users to remove a device from a deviceClass or  a complete deviceClasses.

Goals (aka. expected user outcomes)

User should be able to remove a disk device or a complete deviceClass, in case device is no longer needed, or was added accidentally. Currently, this is a cumbersome procedure requiring the complete removal of the LVMCLuster

Requirements (aka. Acceptance Criteria):

For device removal:

1. Remove an existing single device from a list of devices specified in a deviceClass. The LVM PV of that device needs to be empty/free of data. Its the responsibility of the user to move existing data to the remaining PVs, using pvmove command. Instructions on how to do so need to be provided in the documentation. Its LVMS responsibility to remove the PV from the VG using VG reduce. The implementation needs to validate that the PV is empty before removing it from the VG and provide a detail error message pointing to the pvmove command to remove the data. 

For deviceClass removal:

1. deviceClass can only be removed if the corresponding StorageClass has no PVC/PVs attached to it. Otherwise, removal will be rejected with a corresponding error message. Its the responsibility of the user to delete all PVC/PVs. 

Questions to Answer (Optional):

n/a

Out of Scope

Wiping disks after removal - removed disks will otherwise be untouched, in case there is data on non-lvm owned areas. 

Background

n/a

Customer Considerations

This has been asked for by customers, see linked RFEs

Documentation Considerations

Doc has existing statements that devices/deviceClasses can not be removed. This needs to be changed, and instructions on the requirements / procedures to do so need to be added (maybe in a "day2 operations" section).

Interoperability Considerations

none