Difference between revisions of "Xenapi-sm-volume-driver"

Revision as of 18:25, 10 March 2011

• Launchpad Entry: NovaSpec:xenapi-sm-support
• Created: 1 February 2011
• Contributors: Armando Migliaccio

Summary

Design and implement a new driver for Nova-Volume, based on XenAPI Storage Manager. This will provide basic storage functionality (like volume creation, and destruction) on a number of different storage back-ends, plus it will enable the capability of using more sophisticated storage back-ends for operations like cloning/snapshotting etc. This becomes premium value for service provider clouds or may become differentiator for enterprise private clouds. To have an idea of the benefits of using XenAPI SM to provide back-end storage services, the list below shows some of the storage plugins already supported in XenServer/XCP:

• NFS VHD: SR plugin which stores disks as VHD files on a remote NFS filesystem
• Local VHD on LVM: SR plugin which represents disks as VHD disks on Logical Volumes within a locally-attached Volume Group
• HBA LUN-per-VDI driver: SR plugin which represents LUNs as VDIs sourced by hardware HBA adapters, e.g. hardware-based iSCSI or FC support
• NetApp: SR driver for mapping of LUNs to VDIs on a NETAPP server, providing use of fast snapshot and clone features on the filer
• LVHD over FC: SR plugin which represents disks as VHDs on Logical Volumes within a Volume Group created on an HBA LUN, e.g. hardware-based iSCSI or FC support
• iSCSI: Base ISCSI SR driver, provides a LUN-per-VDI. Does not support creation of VDIs but accesses existing LUNs on a target.
• LVHD over iSCSI: SR plugin which represents disks as Logical Volumes within a Volume Group created on an iSCSI LUN
• EqualLogic: SR driver for mapping of LUNs to VDIs on a EQUALLOGIC array group, providing use of fast snapshot and clone features on the array

Release Note

This section should include a paragraph describing the end-user impact of this change. It is meant to be included in the release notes of the first release in which it is implemented. (Not all of these will actually be included in the release notes, at the release manager's discretion; but writing them is a useful exercise.)

It is mandatory.

Rationale

User stories

Assumptions

Design

By Leveraging Storage Manager plugins for XenServer/XCP, more drivers can be provided to support sophisticated operations like cloning and snapshotting. The idea is that along side drivers like AoE, and iSCSI, a new driver will be added to

Implementation

This section should describe a plan of action (the "how") to implement the changes discussed. Could include subsections like:

UI Changes

Should cover changes required to the UI, or specific UI that is required to implement this

Code Changes

Code changes should include an overview of what needs to change, and in some cases even the specific details.

Migration

Include:

• data migration, if any
• redirects from old URLs to new ones, if any
• how users will be pointed to the new way of doing things, if necessary.

Test/Demo Plan

This need not be added or completed until the specification is nearing beta.

Unresolved issues

This should highlight any issues that should be addressed in further specifications, and not problems with the specification itself; since any specification with problems cannot be approved.

BoF agenda and discussion

Use this section to take notes during the BoF; if you keep it in the approved spec, use it for summarising what was discussed and note any options that were rejected.