Shared Filesystems service

Available since MOSK 24.3 as GA Available since MOSK 22.5 as TechPreview

MOSK Shared Filesystems service (OpenStack Manila) provides Shared Filesystems as a service. The Shared Filesystems service enables you to create and manage shared filesystems in your multi-project cloud environments.

Note

MOSK does not support the Shared Filesystems service for the clusters with Tungsten Fabric as a networking backend.

Service architecture

The Shared FileSystems service consists of manila-api, manila-scheduler, and manila-share services. All these services communicate with each other through the AMQP protocol and store their data in the MySQL database.

manila-api

Provides a stable RESTful API, authenticates and routes requests throughout the Shared Filesystem service

manila-scheduler

Responsible for scheduling and routing requests to the appropriate manila-share service by determining which backend should serve as the destination for a share creation request

manila-share

Responsible for managing Shared Filesystems service devices, specifically the backend ones

The diagram below illustrates how the Shared FileSystems services communicate with each other.

Untitled Diagram

Shared Filesystems drivers

MOSK ensures support for different kind of equipment and shared filesystems by means of special drivers that are part of the manila-share service. Also, these divers determine the ability to restrict access to data stored on a shared filesystem, list of operations with Manila volumes, and types of connections to the client network.

Driver Handles Share Servers (DHSS) is one of the main parameters that define the Manila workflow including the way the Manila driver makes clients access shared filesystems. Some drivers support only one DHSS mode, for example, the LVM share driver. Others support both modes, for example, the Generic driver. If the DHSS is set to False in the driver configuration, the driver does not prepare the share server that provides access to the share filesystems and the server and network setup should be performed by the administrator. In this case, the Shared Filesystems service only manages the server in its own configuration.

Untitled Diagram

If the driver configuration includes DHSS=True, the driver creates a service virtual machine that provides access to shared filesystems. Also, when DHSS=True, the Shared Filesystems service performs a network setup to provide client’s access to the created service virtual machine. For working with the service virtual machine, the Shared Filesystems service requires a separate service network that must be included in the driver’s configuration as well.

Let’s describe the Generic driver as an example for the DHSS=True case. There are two network topologies for connecting client’s network to the service virtual machine, which depend of the connect_share_server_to_tenant_network parameter. If the connect_share_server_to_tenant_network parameter is set to False, which is default, the client must create a shared network connected to a public router. IP addresses from this network will be granted access to the created shared filesystem. The Shared Filesystems service creates a subnet in its service network where the network port of the new service virtual machine and network port of the clent’s router will be connected to. When a new shared filesystem is created, the client’s machine is granted access to it through the router.

Untitled Diagram

If the connect_share_server_to_tenant_network parameter is set to True, the Shared Filesystems service creates the service virtual machines with two network interfaces. One of them is connected to the service network while the other one is connected to the client’s network.

Untitled Diagram

Enabling the Shared Filesystems service

The Shared Filesystems service is not included into the core set of services and needs to be explicitly enabled in the OpenStackDeployment custom resource.

To install the OpenStack Manila services, add the shared-file-system keyword to the spec:features:services list:

spec:
  features:
    services:
      - shared-file-system