StoragePool Metadata Removal

Summary

Until oVirt 3.5 the Storage Pool (Data Center) information was maintained in the engine database and stored in different ways in the Master Domain. In the larger scope of removing the SPM (Storage Pool Manager) and the Master Domain Role, the goal of this feature is to decommission the Storage Pool Metadata (and its dependency on the Master Domain).

Owner

• Name: Federico Simoncelli
• Email: fsimonce@redhat.com

Current status

• Released in oVirt 3.5

Detailed Description

• connectStoragePool will receive a new argument enumerating the storage domains that are part of the pool and their status (domainsMap).
• refreshStoragePool is now useless (as there’s no metadata on the storage anymore), on Data Center 3.5 connectStoragePool will be used also for refreshing.
• Since it’s not possible to periodically refresh the Storage Domains map from the storage anymore it’s now mandatory that all the hosts will receive these information with the connectStoragePool command (especially on the activation/deactivation of the domains). The engine will include a new logic to synchronize the hosts sending connectStoragePool when required (analyzing the VdsStats).
• The new Storage Domain statuses “Preparing For Maintenance”, “Activating” and “Detaching” will be introduced in order to mark those domains that are in transition.
• full compatibility with the old connectStoragePool/refreshStoragePool/reconstructMaster will be maintained for Data Center 3.4 (and lower).

Benefit to oVirt

• This feature will enable the SPM and Master Domain removal.
• Robustness as some complex flows will be dropped (reconstructMaster) and consistency (the metadata is kept in the engine database).