Dell EMC XtremIO Block Storage driver¶

Support matrix¶

XtremIO version 4.x is supported.

Supported operations¶

• Create, delete, clone, attach, and detach volumes.
• Create and delete volume snapshots.
• Create a volume from a snapshot.
• Copy an image to a volume.
• Copy a volume to an image.
• Extend a volume.
• Manage and unmanage a volume.
• Manage and unmanage a snapshot.
• Get volume statistics.
• Create, modify, delete, and list consistency groups.
• Create, modify, delete, and list snapshots of consistency groups.
• Create consistency group from consistency group or consistency group snapshot.
• Volume Migration (host assisted)

XtremIO Block Storage driver configuration¶

Edit the cinder.conf file by adding the configuration below under the [DEFAULT] section of the file in case of a single back end or under a separate section in case of multiple back ends (for example [XTREMIO]). The configuration file is usually located under the following path /etc/cinder/cinder.conf.

For a configuration example, refer to the configuration Configuration example.

san_ip = XMS Management IP

xtremio_cluster_name = Cluster-Name

san_login = XMS username
san_password = XMS username password

Multiple back ends¶

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

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

Setting thin provisioning and multipathing parameters¶

To support thin provisioning and multipathing in the XtremIO Array, the following parameters from the Nova and Cinder configuration files should be modified as follows:

• Thin Provisioning

  All XtremIO volumes are thin provisioned. The default value of 20 should be maintained for the max_over_subscription_ratio parameter.

  The use_cow_images parameter in the nova.conf file should be set to False as follows:

  use_cow_images = False
  

• Multipathing

  The use_multipath_for_image_xfer parameter in the cinder.conf file should be set to True as follows:

  use_multipath_for_image_xfer = True
  

Image service optimization¶

Limit the number of copies (XtremIO snapshots) taken from each image cache.

xtremio_volumes_per_glance_cache = 100

The default value is 100. A value of 0 ignores the limit and defers to the array maximum as the effective limit.

SSL certification¶

To enable SSL certificate validation, modify the following option in the cinder.conf file:

driver_ssl_cert_verify = true

By default, SSL certificate validation is disabled.

To specify a non-default path to CA_Bundle file or directory with certificates of trusted CAs:

driver_ssl_cert_path = Certificate path

Configuring CHAP¶

The XtremIO Block Storage driver supports CHAP initiator authentication and discovery.

If CHAP initiator authentication is required, set the CHAP Authentication mode to initiator.

To set the CHAP initiator mode using CLI, run the following XMCLI command:

$ modify-chap chap-authentication-mode=initiator

If CHAP initiator discovery is required, set the CHAP discovery mode to initiator.

To set the CHAP initiator discovery mode using CLI, run the following XMCLI command:

$ modify-chap chap-discovery-mode=initiator

The CHAP initiator modes can also be set via the XMS GUI.

Refer to XtremIO User Guide for details on CHAP configuration via GUI and CLI.

The CHAP initiator authentication and discovery credentials (username and password) are generated automatically by the Block Storage driver. Therefore, there is no need to configure the initial CHAP credentials manually in XMS.

Configuration example¶

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

[Default]
enabled_backends = XtremIO

[XtremIO]
volume_driver = cinder.volume.drivers.dell_emc.xtremio.XtremIOFibreChannelDriver
san_ip = XMS_IP
xtremio_cluster_name = Cluster01
san_login = XMS_USER
san_password = XMS_PASSWD
volume_backend_name = XtremIOAFA