manila/doc/source/configuration/shared-file-systems/drivers/glusterfs-native-driver.rst

GlusterFS Native driver

GlusterFS Native driver uses GlusterFS, an open source distributed file system, as the storage back end for serving file shares to Shared File Systems service clients.

A Shared File Systems service share is a GlusterFS volume. This driver uses flat-network (share-server-less) model. Instances directly talk with the GlusterFS back end storage pool. The instances use glusterfs protocol to mount the GlusterFS shares. Access to each share is allowed via TLS Certificates. Only the instance which has the TLS trust established with the GlusterFS back end can mount and hence use the share. Currently only read-write (rw) access is supported.

Network approach

L3 connectivity between the storage back end and the host running the Shared File Systems share service should exist.

Multi-tenancy model

The driver does not support network segmented multi-tenancy model. Instead multi-tenancy is supported using tenant specific TLS certificates.

Supported shared filesystems and operations

The driver supports GlusterFS shares.

The following operations are supported:

• Create a share.

• Delete a share.

• Allow share access.

  Note the following limitations:

  • Only access by TLS Certificates (cert access type) is supported.
  • Only read-write access is supported.

• Deny share access.

• Create a snapshot.

• Delete a snapshot.

Requirements

• Install glusterfs-server package, version >= 3.6.x, on the storage back end.
• Install glusterfs and glusterfs-fuse package, version >= 3.6.x, on the Shared File Systems service host.
• Establish network connection between the Shared File Systems service host and the storage back end.

Shared File Systems service driver configuration setting

The following parameters in the Shared File Systems service's configuration file need to be set:

share_driver = manila.share.drivers.glusterfs_native.GlusterfsNativeShareDriver
glusterfs_servers = glustervolserver
glusterfs_volume_pattern = manila-share-volume-\d+$

The parameters are:

glusterfs_servers

List of GlusterFS servers which provide volumes that can be used to create shares. The servers are expected to be of distinct Gluster clusters, so they should not be Gluster peers. Each server should be of the form [<remoteuser>@]<glustervolserver>.

The optional <remoteuser>@ part of the server URI indicates SSH access for cluster management (see related optional parameters below). If it is not given, direct command line management is performed (the Shared File Systems service host is assumed to be part of the GlusterFS cluster the server belongs to).

glusterfs_volume_pattern

Regular expression template used to filter GlusterFS volumes for share creation. The regular expression template can contain the #{size} parameter which matches a number and the value will be interpreted as size of the volume in GB. Examples: manila-share-volume-\d+$, manila-share-volume-#{size}G-\d+$; with matching volume names, respectively: manila-share-volume-12, manila-share-volume-3G-13. In the latter example, the number that matches #{size}, which is 3, is an indication that the size of volume is 3 GB. On share creation, the Shared File Systems service picks volumes at least as large as the requested one.

When setting up GlusterFS shares, note the following:

• GlusterFS volumes are not created on demand. A pre-existing set of GlusterFS volumes should be supplied by the GlusterFS cluster(s), conforming to the naming convention encoded by glusterfs_volume_pattern. However, the GlusterFS endpoint is allowed to extend this set any time, so the Shared File Systems service and GlusterFS endpoints are expected to communicate volume supply and demand out-of-band.
• Certificate setup, also known as trust setup, between instance and storage back end is out of band of the Shared File Systems service.
• For the Shared File Systems service to use GlusterFS volumes, the name of the trashcan directory in GlusterFS volumes must not be changed from the default.