Dell EMC XtremIO Block Storage driver¶
The high performance XtremIO All Flash Array (AFA) offers Block Storage services to OpenStack. Using the driver, OpenStack Block Storage hosts can connect to an XtremIO Storage cluster.
This section explains how to configure and connect the block storage nodes to an XtremIO storage cluster.
XtremIO version 4.x is supported.
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¶
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
Configuration option = Default value
(Integer) Number of retries in case array is busy
(Integer) Interval between retries in case array is busy
(Boolean) Should the driver remove initiator groups with no volumes after the last connection was terminated. Since the behavior till now was to leave the IG be, we default to False (not deleting IGs without connected volumes); setting this parameter to True will remove any IG after terminating its connection to the last volume.
(String) XMS cluster id in multi-cluster environment
(List of String) Allowed ports. Comma separated list of XtremIO iSCSI IPs or FC WWNs (ex. 58:cc:f0:98:49:22:07:02) to be used. If option is not set all ports are allowed.
(Integer) Number of volumes created from each cached glance image
For a configuration example, refer to the configuration Configuration example.
XtremIO driver name¶
Configure the driver name by setting the following parameter in the
volume_driver = cinder.volume.drivers.dell_emc.xtremio.XtremIOISCSIDriver
For Fibre Channel:
volume_driver = cinder.volume.drivers.dell_emc.xtremio.XtremIOFibreChannelDriver
XtremIO management server (XMS) IP¶
To retrieve the management IP, use the show-xms CLI command.
Configure the management IP by adding the following parameter:
san_ip = XMS Management IP
XtremIO cluster name¶
In XtremIO version 4.0, a single XMS can manage multiple cluster back ends. In such setups, the administrator is required to specify the cluster name (in addition to the XMS IP). Each cluster must be defined as a separate back end.
To retrieve the cluster name, run the show-clusters CLI command.
Configure the cluster name by adding the following parameter:
xtremio_cluster_name = Cluster-Name
When a single cluster is managed in XtremIO version 4.0, the cluster name is not required.
XtremIO user credentials¶
OpenStack Block Storage requires an XtremIO XMS user with administrative privileges. XtremIO recommends creating a dedicated OpenStack user account that holds an administrative user role.
Refer to the XtremIO User Guide for details on user account management.
Create an XMS account using either the XMS GUI or the add-user-account CLI command.
Configure the user credentials by adding the following parameters:
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:
All XtremIO volumes are thin provisioned. The default value of 20 should be maintained for the
use_cow_imagesparameter in the
nova.conffile should be set to
use_cow_images = False
use_multipath_for_image_xferparameter in the
cinder.conffile should be set to
Truefor each backend or in
[backend_defaults]section as a common configuration for all backends.
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.
To enable SSL certificate validation, modify the following option in the
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
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.
Configuring ports filtering¶
The XtremIO Block Storage driver supports ports filtering to define a list of iSCSI IP-addresses or FC WWNs which will be used to attach volumes. If option is not set all ports are allowed.
xtremio_ports = iSCSI IPs or FC WWNs
You can update the
cinder.conf file by editing the necessary parameters as
[Default] enabled_backends = XtremIO [XtremIO] volume_driver = cinder.volume.drivers.dell_emc.xtremio.XtremIOFibreChannelDriver san_ip = XMS_IP xtremio_cluster_name = Cluster01 xtremio_ports = 21:00:00:24:ff:57:b2:36,21:00:00:24:ff:57:b2:55 san_login = XMS_USER san_password = XMS_PASSWD volume_backend_name = XtremIOAFA