12 KiB
Dell EMC Unity driver
The EMC Shared File Systems service driver framework (EMCShareDriver) utilizes the EMC storage products to provide the shared file systems to OpenStack. The EMC driver is a plug-in based driver which is designed to use different plug-ins to manage different EMC storage products.
The Unity plug-in manages the Unity system to provide shared filesystems. The EMC driver framework with the Unity plug-in is referred to as the Unity driver in this document.
This driver performs the operations on Unity through RESTful APIs. Each backend manages one Storage Processor of Unity. Configure multiple Shared File Systems service backends to manage multiple Unity systems.
Requirements
- Unity OE 4.1.x 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 shared filesystems and 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.
- Create/Delete snapshot of a share.
- Create a new share from snapshot.
- Revert a share to a snapshot.
Supported Network Topologies
Flat
This type is fully supported by Unity share driver, however flat networks are restricted due to the limited number of tenant networks that can be created from them.
VLAN
We recommend this type of network topology in Manila. In most use cases, VLAN is used to isolate the different tenants and provide an isolated network for each tenant. To support this function, an administrator needs to set a slot connected with Unity Ethernet port in
Trunk
mode or allow multiple VLANs from the slot.VXLAN
Unity native VXLAN is still unavailable. However, with the HPB (Hierarchical Port Binding) in Networking and Shared file system services, it is possible that Unity co-exists with VXLAN enabled network environment.
Pre-Configurations
On Manila Node
Python library storops
is required to run Unity driver.
Install it with the pip
command. You may need root
privilege to install python libraries.
pip install storops
On Unity System
Configure system level NTP server.
Open
Unisphere
of your Unity system and navigate to:Unisphere -> Settings -> Management -> System Time and NTP
Select
Enable NTP synchronization
and add your NTP server(s).The time on the Unity system and the Active Directory domains used in security services should be in sync. We recommend using the same NTP server on both the Unity system and Active Directory domains.
Configure system level DNS server.
Open
Unisphere
of your Unity system and navigate to:Unisphere -> Settings -> Management -> DNS Server
Select
Configure DNS server address manually
and add your DNS server(s).
Backend 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.
Supported MTU size
Unity currently only supports 1500 and 9000 as the mtu size, the user can change the above mtu size from Unity Unisphere:
- In the Unisphere, go to Settings, Access, and then Ethernet.
- Double click the ethernet port.
- Select the MTU size from the drop down list.
The Unity driver will select the port where mtu is equal to the mtu of share network during share server creation.
IPv6 support
IPv6 support for Unity driver is introduced in Queens release. The feature is divided into two parts:
- The driver is able to manage share or snapshot in the Neutron IPv6 network.
- The driver is able to connect Unity management interface using its IPv6 address.
Pre-Configurations for IPv6 support
The following parameters need to be configured in /etc/manila/manila.conf for the Unity driver:
network_plugin_ipv6_enabled = True
- network_plugin_ipv6_enabled indicates IPv6 is enabled.
If you want to connect Unity using IPv6 address, you should configure IPv6 address by /net/if/mgmt uemcli command, mgmtInterfaceSettings RESTful api or the system settings of Unity GUI for Unity and specify the address in `/etc/manila/manila.conf`:
emc_nas_server = <IPv6 address>
Supported share creation in mode that driver does not create and destroy share servers (DHSS=False)
To create a file share in this mode, you need to:
Create NAS server with network interface in Unity system.
Set 'driver_handles_share_servers=False' and 'unity_share_server' in
/etc/manila/manila.conf
:driver_handles_share_servers = False unity_share_server = <name of NAS server in Unity system>
Specify the share type with driver_handles_share_servers = False extra specification:
$ manila type-create <share_type_name> False
Create share.
$ manila create <share_protocol> <size> --name <share_name> --share-type <share_type_name>
Note
Do not specify the share network in share creation command because no share servers will be created. Driver will use the unity_share_server specified for share creation.
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:
- The driver is able to create/delete snapshot of share.
- The driver is able to create share from snapshot.
Pre-Configurations for Snapshot support
The following extra specifications need to be configured with share type.
- snapshot_support = True
- create_share_from_snapshot_support = True
For new share type, these extra specifications can be set directly when creating share type:
manila type-create --snapshot_support True --create_share_from_snapshot_support True ${share_type_name} True
Or you can update already existing share type with command:
manila type-key ${share_type_name} set snapshot_support=True
manila type-key ${share_type_name} set create_share_from_snapshot_support=True
To snapshot a share and create share from the snapshot
Firstly, you need create a share from share type that has extra specifications(snapshot_support=True, create_share_from_snapshot_support=True). Then snapshot the share with command:
manila snapshot-create ${source_share_name} --name ${target_snapshot_name} --description " "
After creating the snapshot from previous step, you can create share from that snapshot. Use command:
manila create nfs 1 --name ${target_share_name} --metadata source=snapshot --description " " --snapshot-id ${source_snapshot_id}
Supported security services
Unity share driver provides IP
based authentication
method support for NFS
shares and user
based
authentication method for CIFS
shares respectively. For
CIFS
share, Microsoft Active Directory is the only
supported security service.
IO Load balance
The Unity driver automatically distributes the file interfaces per
storage processor based on the option unity_ethernet_ports
.
This balances IO traffic. The recommended configuration for
unity_ethernet_ports
specifies balanced ports per storage
processor. For example:
# Use eth2 from both SPs
unity_ethernet_ports = spa_eth2, spb_eth2
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.
Driver options
Configuration options specific to this driver: