Unity Driver

EMC manila driver framework (EMCShareDriver) utilizes the EMC storage products to provide the shared filesystems to OpenStack. The EMC manila driver is a plugin based driver which is designed to use different plugins to manage different EMC storage products.

Unity plugin is the plugin which manages the Unity Storage System to provide shared filesystems. EMC driver framework with Unity plugin is referred to as Unity driver in this document.

This driver performs the operations on Unity by REST API. Each backend manages one Unity Storage System. Multiple manila backends need to be configured to manage multiple Unity Storage Systems.

Requirements

  • Unity OE 4.0.1 or higher.

  • StorOps 1.1.0 or higher is installed on Manila node.

  • Following licenses are activated on Unity:

    • CIFS/SMB Support

    • Network File System (NFS)

    • Thin Provisioning

    • Fiber Channel (FC)

    • Internet Small Computer System Interface (iSCSI)

Supported Operations

In detail, users are allowed to do following operation with EMC Unity Storage Systems.

  • Create/delete a NFS share.

  • Create/delete a CIFS share.

  • Extend the size of a share.

  • Shrink the size of a share.

  • Modify the host access privilege of a NFS share.

  • Modify the user access privilege of a CIFS share.

  • Take/Delete snapshot of a share.

  • Create a new share from snapshot.

  • Revert a share to a snapshot.

Supported Network Topologies

  • flat

  • VLAN

Pre-Configurations

On Manila Node

StorOps library is required to run Unity driver. Please install it with the pip command. You may need root privilege to install python libraries.

pip install storops

On Unity System

  1. Configure System level NTP Server

Configure the NTP server for your Unity at:

Unisphere -> Settings -> Management -> System Time and NTP

Select “Enable NTP synchronization” and add your NTP server(s).

  1. Configure System level DNS Server

Configure the DNS server for your Unity at:

Unisphere -> Settings -> Management -> DNS Server

Select “Configure DNS server address manually” and add your DNS server(s).

Configurations

Following configurations need to be configured in /etc/manila/manila.conf for the Unity driver.

share_driver = manila.share.drivers.dell_emc.driver.EMCShareDriver
emc_share_backend = unity
emc_nas_server = <management IP address of the Unity system>
emc_nas_login = <user with administrator privilege>
emc_nas_password = <password>
unity_server_meta_pool = <pool name>
unity_share_data_pools = <comma separated pool names>
unity_ethernet_ports = <comma separated ports list>
driver_handles_share_servers = True/False
unity_share_server = <name of NAS server in Unity system>
  • emc_share_backend

    The plugin name. Set it to unity for the Unity driver.

  • emc_nas_server

    The management IP for Unity.

  • unity_server_meta_pool

    The name of the pool to persist the meta-data of NAS server. This option is required.

  • unity_share_data_pools

    Comma separated list specifying the name of the pools to be used by this backend. Do not set this option if all storage pools on the system can be used. Wild card character is supported.

    Examples:

    # Only use pool_1
unity_share_data_pools = pool_1
# Only use pools whose name stars from pool_
unity_share_data_pools = pool_*
# Use all pools on Unity
unity_share_data_pools = *
  • unity_ethernet_ports

    Comma separated list specifying the ethernet ports of Unity system that can be used for share. Do not set this option if all ethernet ports can be used. Wild card character is supported. Both the normal ethernet port and link aggregation port can be used by Unity share driver.

    Examples:

    # Only use spa_eth1
unity_ethernet_ports = spa_eth1
# Use port whose name stars from spa_
unity_ethernet_ports = spa_*
# Use all Link Aggregation ports
unity_ethernet_ports = sp*_la_*
# Use all available ports
unity_ethernet_ports = *
  • driver_handles_share_servers

    Unity driver requires this option to be as True or False. Need to set unity_share_server when the value is False.

  • unity_share_server

    One of NAS server names in Unity, it is used for share creation when the driver is in DHSS=False mode.

Restart of manila-share service is needed for the configuration changes to take effect.

IPv6 support

IPv6 support for Unity driver is introduced in Queens release. The feature is divided into two parts:

  1. The driver is able to manage share or snapshot in the Neutron IPv6 network.

  2. The driver is able to connect Unity management interface using its IPv6 address.

Snapshot support

In the Mitaka and Newton release of OpenStack, Snapshot support is enabled by default for a newly created share type. Starting with the Ocata release, the snapshot_support extra spec must be set to True in order to allow snapshots for a share type. If the ‘snapshot_support’ extra_spec is omitted or if it is set to False, users would not be able to create snapshots on shares of this share type. The feature is divided into two parts:

  1. The driver is able to create/delete snapshot of share.

  2. The driver is able to create share from snapshot.

Restrictions

The Unity driver has following restrictions.

  • EMC Unity does not support the same IP in different VLANs.

  • Only IP access type is supported for NFS.

  • Only user access type is supported for CIFS.

API Implementations

Following driver features are implemented in the plugin.

  • create_share: Create a share and export it based on the protocol used (NFS or CIFS).

  • create_share_from_snapshot: Create a share from a snapshot - clone a snapshot.

  • delete_share: Delete a share.

  • extend_share: Extend the maximum size of a share.

  • shrink_share: Shrink the minimum size of a share.

  • create_snapshot: Create a snapshot for the specified share.

  • delete_snapshot: Delete the snapshot of the share.

  • update_access: recover, add or delete user/host access to a share.

  • allow_access: Allow access (read write/read only) of a user to a CIFS share. Allow access (read write/read only) of a host to a NFS share.

  • deny_access: Remove access (read write/read only) of a user from a CIFS share. Remove access (read write/read only) of a host from a NFS share.

  • ensure_share: Check whether share exists or not.

  • update_share_stats: Retrieve share related statistics from Unity.

  • get_network_allocations_number: Returns number of network allocations for creating VIFs.

  • setup_server: Set up and configures share server with given network parameters.

  • teardown_server: Tear down the share server.

  • revert_to_snapshot: Revert a share to a snapshot.

The manila.share.drivers.dell_emc.driver Module

EMC specific NAS storage driver. This driver is a pluggable driver that allows specific EMC NAS devices to be plugged-in as the underlying backend. Use the Manila configuration variable “share_backend_name” to specify, which backend plugins to use.

class EMCShareDriver(*args, **kwargs)

Bases: manila.share.driver.ShareDriver

EMC specific NAS driver. Allows for NFS and CIFS NAS storage usage.

allow_access(context, share, access, share_server=None)

Allow access to the share.

check_for_setup_error()

Check for setup error.

create_share(context, share, share_server=None)

Is called to create share.

create_share_from_snapshot(context, share, snapshot, share_server=None)

Is called to create share from snapshot.

create_snapshot(context, snapshot, share_server=None)

Is called to create snapshot.

delete_share(context, share, share_server=None)

Is called to remove share.

delete_snapshot(context, snapshot, share_server=None)

Is called to remove snapshot.

deny_access(context, share, access, share_server=None)

Deny access to the share.

do_setup(context)

Any initialization the share driver does while starting.

ensure_share(context, share, share_server=None)

Invoked to sure that share is exported.

extend_share(share, new_size, share_server=None)

Is called to extend share.

get_configured_ip_versions()

“Get allowed IP versions.

The supported versions are returned with list, possible values are: [4], [6], or [4, 6]

Drivers that assert ipv6_implemented = True must override this method. If the returned list includes 4, then shares created by this driver must have an IPv4 export location. If the list includes 6, then shares created by the driver must have an IPv6 export location.

Drivers should check that their storage controller actually has IPv4/IPv6 enabled and configured properly.

get_network_allocations_number()

Returns number of network allocations for creating VIFs.

revert_to_snapshot(context, snapshot, share_access_rules, snapshot_access_rules, share_server=None)

Reverts a share (in place) to the specified snapshot.

Does not delete the share snapshot. The share and snapshot must both be ‘available’ for the restore to be attempted. The snapshot must be the most recent one taken by Manila; the API layer performs this check so the driver doesn’t have to.

The share must be reverted in place to the contents of the snapshot. Application admins should quiesce or otherwise prepare the application for the shared file system contents to change suddenly.

Parameters

  • context – Current context

  • snapshot – The snapshot to be restored

  • share_access_rules – List of all access rules for the affected share

  • snapshot_access_rules – List of all access rules for the affected snapshot

  • share_server – Optional – Share server model or None

shrink_share(share, new_size, share_server=None)

Is called to shrink share.

update_access(context, share, access_rules, add_rules, delete_rules, share_server=None)

Update access to the share.

The manila.share.drivers.dell_emc.plugins.unity.connection Module

Unity backend for the EMC Manila driver.

class UnityStorageConnection(*args, **kwargs)

Bases: manila.share.drivers.dell_emc.plugins.base.StorageConnection

Implements Unity specific functionality for EMC Manila driver.

IP_ALLOCATIONS = 1
allow_access(context, share, access, share_server=None)

Allow access to a share.

check_for_setup_error()

Check for setup error.

clear_access(share, white_list=None)
connect(emc_share_driver, context)

Connect to Unity storage.

create_share(context, share, share_server=None)

Create a share and export it based on protocol used.

create_share_from_snapshot(context, share, snapshot, share_server=None)

Create a share from a snapshot - clone a snapshot.

create_snapshot(context, snapshot, share_server=None)

Create snapshot from share.

delete_share(context, share, share_server=None)

Delete a share.

delete_snapshot(context, snapshot, share_server=None)

Delete a snapshot.

deny_access(context, share, access, share_server)

Deny access to a share.

ensure_share(context, share, share_server)

Ensure that the share is exported.

extend_share(share, new_size, share_server=None)

Invoked to extend share.

get_network_allocations_number()

Returns number of network allocations for creating VIFs.

get_pool(share)

Get the pool name of the share.

get_server_name(share_server=None)
revert_to_snapshot(context, snapshot, share_access_rules, snapshot_access_rules, share_server=None)

Reverts a share (in place) to the specified snapshot.

setup_server(network_info, metadata=None)

Set up and configures share server with given network parameters.

shrink_share(share, new_size, share_server=None)

Shrinks a share to new size.

Parameters

  • share – Share that will be shrunk.

  • new_size – New size of share.

  • share_server – Data structure with share server information. Not used by this driver.

teardown_server(server_details, security_services=None)

Teardown share server.

update_access(context, share, access_rules, add_rules, delete_rules, share_server=None)

Update access rules for given share.

update_share_stats(stats_dict)

Communicate with EMCNASClient to get the stats.

static validate_network(network_info)
validate_port_configuration(port_ids_conf)

Initializes the SP and ports based on the port option.