175 lines
4.5 KiB
ReStructuredText
175 lines
4.5 KiB
ReStructuredText
..
|
|
This work is licensed under a Creative Commons Attribution 3.0 Unported
|
|
License.
|
|
|
|
http://creativecommons.org/licenses/by/3.0/legalcode
|
|
|
|
=================
|
|
SMB Volume Driver
|
|
=================
|
|
|
|
https://blueprints.launchpad.net/cinder/+spec/smbfs-volume-driver
|
|
|
|
Currently, there are Cinder volume drivers which make use of network-attached
|
|
storage file systems such as GlusterFS of NFS. The purpose of this blueprint
|
|
is adding a volume driver supporting SMB based volume backends.
|
|
|
|
Problem description
|
|
===================
|
|
|
|
SMB is a widely used protocol, especially in the Microsoft world. Its
|
|
simplicity along with the big improvements that were introduced in SMB 3
|
|
make this type of volume backend a very good alternative.
|
|
|
|
SMB 3 brings features such as transparent failover, multichanneling using
|
|
multiple NICs, encrypted communication, and RDMA.
|
|
|
|
Recent versions of Samba got improved support of the SMB 3 protocol, as well
|
|
as Active Directory integration.
|
|
|
|
This driver will be backwards compatible, supporting older versions of SMB.
|
|
It will support using any type of SMB share, including:
|
|
|
|
- from Scale-Out file servers to basic Windows shares;
|
|
|
|
- Linux Samba shares;
|
|
|
|
- vendor specific hardware exporting SMB shares.
|
|
|
|
Use Cases
|
|
=========
|
|
|
|
Proposed change
|
|
===============
|
|
|
|
The proposed driver will make use of Samba in order to mount and make use of
|
|
SMB shares in a secure way, supporting Active Directory based authentication.
|
|
|
|
This driver will include all the features required by the Juno release. It
|
|
will have a similar flow with other netowrk attached file system drivers,
|
|
managing images regarded as volumes while hosted on SMB shares.
|
|
|
|
It will include support for raw, qcow2, vhd and vhdx images. Even so, because
|
|
it will use qemu-img for image related operations, it will not support yet
|
|
snapshots for vhd and vhdx formats because of qemu-img's limitations.
|
|
|
|
The snapshot management will be done in a similar way as the Gluster driver,
|
|
using an additional ".info" file containing mappings between snapshot ids and
|
|
their actual paths. This is required as the path can change in time (for
|
|
example when deleting a snapshot from the chain, the backing file will be
|
|
changed).
|
|
|
|
Another driver based on this will be proposed for Windows environments, having
|
|
full vhd/vhdx support.
|
|
|
|
Alternatives
|
|
------------
|
|
|
|
None
|
|
|
|
Data model impact
|
|
-----------------
|
|
|
|
None
|
|
|
|
REST API impact
|
|
---------------
|
|
|
|
None
|
|
|
|
Security impact
|
|
---------------
|
|
|
|
None
|
|
|
|
Notifications impact
|
|
--------------------
|
|
|
|
None
|
|
|
|
Other end user impact
|
|
---------------------
|
|
|
|
None
|
|
|
|
Performance Impact
|
|
------------------
|
|
|
|
The driver will periodically ensure that the chosen shares are mounted and also
|
|
retrieve informations such as free space or total allocated space.
|
|
|
|
Certain volume related operations will require to be synchronized.
|
|
|
|
In order to use local shares, the share paths will be read from the Samba
|
|
config file.
|
|
|
|
Other deployer impact
|
|
---------------------
|
|
|
|
The user will provide a list of SMB shares on which volumes may reside. This
|
|
list will be placed in a file located at a path configured in the cinder config
|
|
file. This share list may contain SMB mount options such as flags or
|
|
credentials.
|
|
|
|
The config file will also contain the path to the Samba config file. Oversubmit
|
|
and used space ratios may also be configured.
|
|
|
|
The user will be able to choose the volume type that will be used as well as
|
|
choosing whether to use sparsed or qcow2 files instead of raw files. Depending
|
|
on the available qemu-img version, vhd and vhdx formats may also be used.
|
|
|
|
The volume type may be parsed as extra spec when creating a volume.
|
|
|
|
Developer impact
|
|
----------------
|
|
|
|
None
|
|
|
|
Implementation
|
|
==============
|
|
|
|
Assignee(s)
|
|
-----------
|
|
|
|
Primary assignee:
|
|
<lpetrut@cloudbasesolutions.com>
|
|
|
|
Other contributors:
|
|
<gsamfira@cloudbasesoltions.com>
|
|
|
|
Work Items
|
|
----------
|
|
|
|
Provide support for mounting SMB shares in the remotefs client and also using
|
|
local shares.
|
|
|
|
Get SMB share status such as free space or allocated space.
|
|
|
|
Provide volume related operations support using images hosted on SMB shares.
|
|
|
|
Dependencies
|
|
============
|
|
|
|
Libvirt smbfs volume driver blueprint:
|
|
https://blueprints.launchpad.net/nova/+spec/libvirt-smbfs-volume-support
|
|
|
|
Hyper-V smbfs volume driver blueprint:
|
|
https://blueprints.launchpad.net/nova/+spec/hyper-v-smbfs-volume-support
|
|
|
|
Testing
|
|
=======
|
|
|
|
A Cinder CI will be testing the SMB related features.
|
|
|
|
Documentation Impact
|
|
====================
|
|
|
|
Using the SMB backend will be documented.
|
|
|
|
References
|
|
==========
|
|
|
|
Samba wiki page:
|
|
https://wiki.samba.org/index.php/Main_Page
|
|
|