Hi, the YaST team has the idea to make some storage tasks simpler to use by introducing storage wizards.
Attached are the first brain storming results. Feedback is wanted. ciao Arvin -- Arvin Schnell, <[email protected]> Senior Software Engineer, Research & Development SUSE Software Solutions Germany GmbH Maxfeldstraße 5 90409 Nürnberg Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Felix Imendörffer
Storage Wizards =============== The idea is to make some common tasks easier for the user by providing wizards. Adding features that are not possible yet is out-of-scope. So far this is a brain storming not anything like a plan or even road map. One generic problem the YaST team faces everlasting is that we do not know for sure what our users are doing with YaST and we lack use-cases. Solving that problem is also out-of-scope. Generic Wizards =============== Generic wizards can be used during installation and in the running system. Creating RAID ------------- Although the workflow for creating RAIDs seems easy (select devices, RAID level and use of it) there is often a tedious task required before using it: The recommendation is to use partitions not entire disks. When several RAIDs using the same disks are needed the use of partitions is a hard requirement. Creating several partitions is tedious. The clone tool cannot always be used. Also, the user might have to calculate the size of the partitions so that the resulting RAID has the required size. These steps could be improved by a wizard: The user just selects a few disks and the size the RAID should have. YaST then creates the partitions with the required size. Such a wizard could make it easy to create three RAIDs with different levels for /, /boot and /home. Creating Bcache --------------- Creating a bcache could be done with a wizard like creating RAIDs. The data the user has to provide could be the disks, the size of the resulting device and the fraction the cache device has. Creating LVM Volume Group and Btrfs ----------------------------------- Also creating a LVM volume group or a btrfs could be done with a wizard that automatically allows to create partitions of desired size. Improved subvolume handling with RAID levels and quota is already under research independent of this document about wizards. Storage Pools ------------- Suppose the user wants to create three RAIDs over four disks. Why specify the four disks three times? The user could first define a pool of those disks and when creating the RAIDs just specify the pool of disks to use. In that case YaST would find suitable space on the disks. The user would tell YaST that e.g. a RAID5 of size 1 TiB using four devices from a certain pool has to be created. The same idea for bcache would create a bcache device with the backing from one pool and the cache from another pool. And for LVM one could create a volume group of a certain size spread equally over three disks - e.g. if later LVM RAID logical volumes are desired. YaST would save the definition of the pools for later reuse. And YaST could also auto-generate two pools: One for HDDs and one for SSDs. Abstraction ----------- In the end YaST could even decide for the user which storage technologies to use. The user could just specify: "I want an 8 TiB XFS filesystem with RAID5 redundancy on 6 disks and snapshot support." YaST then decides to create a RAID5 with LVM and a thin-pool. Additionally the user could set preferences, e.g. whether to use bcache or LVM cache, MD RAID or LVM RAID. But so far YaST only supports one of those technologies. These concepts might remind you about other projects. Proposal Wizards ================ Proposal wizards can only be used during installation. Manual Space Maker ------------------ Often an important part of the proposal is to decide what existing partitions can be deleted. Sometimes user do not like the result. A wizard should allow the user to select partitions, in general devices, that can be deleted. After this step the proposal code tries to generate a proposal. Control Sizes ------------- Some users are not satisfied with the sizes the proposal uses for the root, home and swap partitions. Better control of these would be nice. But this looks more like some additional parameters for the proposal than a wizard. Further Technologies -------------------- The proposal could make use of further technologies, e.g. RAID and bcache. This again looks more like some additional parameters for the proposal than a wizard.
