Dell EMC ScaleIO Block Storage driver¶

Support matrix¶

Deployment prerequisites¶

• ScaleIO Gateway must be installed and accessible in the network. For installation steps, refer to the Preparing the installation Manager and the Gateway section in ScaleIO Deployment Guide. See Official documentation.
• ScaleIO Data Client (SDC) must be installed on all OpenStack nodes.

Supported operations¶

• Create, delete, clone, attach, detach, manage, and unmanage volumes
• Create, delete, manage, and unmanage volume snapshots
• Create a volume from a snapshot
• Copy an image to a volume
• Copy a volume to an image
• Extend a volume
• Get volume statistics
• Create, list, update, and delete consistency groups
• Create, list, update, and delete consistency group snapshots

ScaleIO QoS support¶

QoS support for the ScaleIO driver includes the ability to set the following capabilities in the Block Storage API cinder.api.contrib.qos_specs_manage QoS specs extension module:

• maxIOPS
• maxIOPSperGB
• maxBWS
• maxBWSperGB

The QoS keys above must be created and associated with a volume type. For information about how to set the key-value pairs and associate them with a volume type, run the following commands:

$ openstack help volume qos

maxIOPS

The QoS I/O rate limit. If not set, the I/O rate will be unlimited. The setting must be larger than 10.

maxIOPSperGB

The QoS I/O rate limit. The limit will be calculated by the specified value multiplied by the volume size. The setting must be larger than 10.

maxBWS

The QoS I/O bandwidth rate limit in KBs. If not set, the I/O bandwidth rate will be unlimited. The setting must be a multiple of 1024.

maxBWSperGB

The QoS I/O bandwidth rate limit in KBs. The limit will be calculated by the specified value multiplied by the volume size. The setting must be a multiple of 1024.

The driver always chooses the minimum between the QoS keys value and the relevant calculated value of maxIOPSperGB or maxBWSperGB.

Since the limits are per SDC, they will be applied after the volume is attached to an instance, and thus to a compute node/SDC.

ScaleIO thin provisioning support¶

The Block Storage driver supports creation of thin-provisioned and thick-provisioned volumes. The provisioning type settings can be added as an extra specification of the volume type, as follows:

provisioning:type = thin\thick

The old specification: sio:provisioning_type is deprecated.

sio_max_over_subscription_ratio = OVER_SUBSCRIPTION_RATIO

san_thin_provision = false

ScaleIO Block Storage driver configuration¶

Edit the cinder.conf file by adding the configuration below under a new section (for example, [scaleio]) and change the enable_backends setting (in the [DEFAULT] section) to include this new back end. The configuration file is usually located at /etc/cinder/cinder.conf.

For a configuration example, refer to the example cinder.conf .

volume_driver = cinder.volume.drivers.dell_emc.scaleio.driver.ScaleIODriver

san_ip = ScaleIO GATEWAY IP

sio_storage_pools = Comma-separated list of protection domain:storage pool name

san_login = ScaleIO username

san_password = ScaleIO password

Multiple back ends¶

Configuring multiple storage back ends allows you to create several back-end storage solutions that serve the same Compute resources.

When a volume is created, the scheduler selects the appropriate back end to handle the request, according to the specified volume type.

Configuration example¶

cinder.conf example file

You can update the cinder.conf file by editing the necessary parameters as follows:

[Default]
enabled_backends = scaleio

[scaleio]
volume_driver = cinder.volume.drivers.dell_emc.scaleio.driver.ScaleIODriver
volume_backend_name = scaleio
san_ip = GATEWAY_IP
sio_storage_pools = Domain1:Pool1,Domain2:Pool2
san_login = SIO_USER
san_password = SIO_PASSWD
san_thin_provision = false

Connector configuration¶

Before using attach/detach volume operations VxFlex OS connector must be properly configured. On each node where VxFlex OS SDC is installed do the following:

1. Create /opt/emc/scaleio/openstack/connector.conf if it does not exist.

   $ mkdir -p /opt/emc/scaleio/openstack
   $ touch /opt/emc/scaleio/openstack/connector.conf
   

2. For each VxFlex OS section in the cinder.conf create the same section in the /opt/emc/scaleio/openstack/connector.conf and populate it with passwords. Example:

   [vxflexos]
   san_password = SIO_PASSWD
   
   [vxflexos-new]
   san_password = SIO2_PASSWD
   

Configuration options¶

The ScaleIO driver supports these configuration options: