IBM Spectrum Virtualize family volume driver¶
The volume management driver for Spectrum Virtualize family offers various block storage services. It provides OpenStack Compute instances with access to IBM Spectrum Virtualize family storage products. These products include the IBM SAN Volume Controller and IBM FlashSystem family members built with IBM Spectrum Virtualize (including FlashSystem 5xxx, 7200, 9100, 9200, 9200R).
For specific product publications, see IBM Documentation.
IBM Spectrum Virtualize family is formerly known as IBM Storwize. As a result, the product code contains ‘Storwize’ terminology and prefixes.
The IBM Spectrum Virtualize family volume driver supports the following block storage service volume operations:
Create, list, delete, attach (map), and detach (unmap) volumes.
Create, list, and delete volume snapshots.
Copy an image to a volume.
Copy a volume to an image.
Clone a volume.
Extend a volume.
Retype a volume.
Create a volume from a snapshot.
Create, list, and delete consistency group.
Create, list, and delete consistency group snapshot.
Modify consistency group (add or remove volumes).
Create consistency group from source (source can be a CG or CG snapshot)
Manage an existing volume.
Failover-host for replicated back ends.
Failback-host for replicated back ends.
Create, list, and delete replication group.
Enable, disable replication group.
Failover, failback replication group.
Configure the Spectrum Virtualize family system¶
The Spectrum Virtualize family system must be configured for iSCSI, Fibre Channel, or both.
If using iSCSI, each Spectrum Virtualize family node should have at least one iSCSI IP address. The Spectrum Virtualize family driver uses an iSCSI IP address associated with the volume’s preferred node (if available) to attach the volume to the instance, otherwise it uses the first available iSCSI IP address of the system. The driver obtains the iSCSI IP address directly from the storage system. You do not need to provide these iSCSI IP addresses directly to the driver.
If using iSCSI, ensure that the compute nodes have iSCSI network access to the Spectrum Virtualize family system.
If using Fibre Channel (FC), each Spectrum Virtualize family node should have at least one WWPN port configured. The driver uses all available WWPNs to attach the volume to the instance. The driver obtains the WWPNs directly from the storage system. You do not need to provide these WWPNs directly to the driver.
If using FC, ensure that the compute nodes have FC connectivity to the Spectrum Virtualize family system.
iSCSI CHAP authentication¶
If using iSCSI for data access and the
storwize_svc_iscsi_chap_enabled is set to
True, the driver will
associate randomly-generated CHAP secrets with all hosts on the Spectrum
Virtualize family. The compute nodes use these secrets when creating
CHAP secrets are added to existing hosts as well as newly-created ones. If the CHAP option is enabled, hosts will not be able to access the storage without the generated secrets.
Not all OpenStack Compute drivers support CHAP authentication. Please check compatibility before using.
CHAP secrets are passed from OpenStack Block Storage to Compute in clear text. This communication should be secured to ensure that CHAP secrets are not discovered.
Configure storage pools¶
The IBM Spectrum Virtualize family driver can allocate volumes in multiple
pools. The pools should be created in advance and be provided to the driver
storwize_svc_volpool_name configuration flag in the form
of a comma-separated list.
For the complete list of configuration flags, see Spectrum Virtualize family driver options in cinder.conf.
Configure user authentication for the driver¶
The driver requires access to the Spectrum Virtualize family system
management interface. The driver communicates with the management using
SSH. The driver should be provided with the Spectrum Virtualize family
management IP using the
san_ip flag, and the management port should
be provided by the
san_ssh_port flag. By default, the port value is
configured to be port 22 (SSH). Also, you can set the secondary
management IP using the
Make sure the compute node running the cinder-volume management driver has SSH network access to the storage system.
To allow the driver to communicate with the Spectrum Virtualize family system, you must provide the driver with a user on the storage system. The driver has two authentication methods: password-based authentication and SSH key pair authentication. The user should have an Administrator role. It is suggested to create a new user for the management driver. Please consult with your storage and security administrator regarding the preferred authentication method and how passwords or SSH keys should be stored in a secure manner.
When creating a new user on the Spectrum Virtualize family system, make sure the user belongs to the Administrator group or to another group that has an Administrator role.
If using password authentication, assign a password to the user on the
Spectrum Virtualize family system. The driver configuration flags for the user
and password are
If you are using the SSH key pair authentication, create SSH private and
public keys using the instructions below or by any other method.
Associate the public key with the user by uploading the public key:
select the choose file option in the Spectrum Virtualize family
management GUI under SSH public key. Alternatively, you may
associate the SSH public key using the command-line interface; details can
be found in the Spectrum Virtualize family documentation. The private key
should be provided to the driver using the
Create a SSH key pair with OpenSSH¶
You can create an SSH key pair using OpenSSH, by running:
$ ssh-keygen -t rsa
The command prompts for a file to save the key pair. For example, if you
key as the filename, two files are created:
key file holds the private SSH key and
holds the public SSH key.
The command also prompts for a pass phrase, which should be empty.
The private key file should be provided to the driver using the
san_private_key configuration flag. The public key should be
uploaded to the Spectrum Virtualize family system using the storage
management GUI or command-line interface.
Ensure that Cinder has read permissions on the private key file.
Configure the Spectrum Virtualize family driver¶
Enable the Spectrum Virtualize family driver¶
Set the volume driver to the Spectrum Virtualize family driver by setting
volume_driver option in the
cinder.conf file as follows:
[svc1234] volume_driver = cinder.volume.drivers.ibm.storwize_svc.storwize_svc_iscsi.StorwizeSVCISCSIDriver san_ip = 188.8.131.52 san_login = superuser san_password = passw0rd storwize_svc_volpool_name = cinder_pool1 volume_backend_name = svc1234
[svc1234] volume_driver = cinder.volume.drivers.ibm.storwize_svc.storwize_svc_fc.StorwizeSVCFCDriver san_ip = 184.108.40.206 san_login = superuser san_password = passw0rd storwize_svc_volpool_name = cinder_pool1 volume_backend_name = svc1234
Add the following to the back-end specification to specify another storage to replicate to:
replication_device = backend_id:rep_svc, san_ip:220.127.116.11, san_login:superuser, san_password:passw0rd, pool_name:cinder_pool1
backend_id is a unique name of the remote storage, the
san_password is authentication information for the
remote storage. The
pool_name is the pool name for the replication
replication_device can be configured for one back end
storage since only one replication target is supported now.
Spectrum Virtualize family driver options in cinder.conf¶
The following options specify default values for all volumes. Some can be over-ridden using volume types, which are described below.
IBM Spectrum Virtualize family is formerly known as IBM Storwize. As a result, the product code contains ‘Storwize’ terminology and prefixes.
Configuration option = Default value
(String) IP address of SAN controller.
(String) Username for SAN controller.
(String) Password for SAN controller.
(String) Filename of private key to use for SSH authentication.
(Port number) SSH port to use with SAN.
(Integer) SSH connection timeout in seconds.
(Integer) Minimum SSH connections in the pool.
(Integer) Maximum SSH connections in the pool.
(String) Specifies secondary management IP or hostname to be used if san_ip is invalid or becomes inaccessible.
(Boolean) Allow tenants to specify QoS on create.
(Integer) Specifies the Spectrum Virtualize Family FlashCopy copy rate to be used when creating a full volume copy. The default is rate is 50, and the valid rates are 1-100.
(Integer) Maximum number of seconds to wait for FlashCopy to be prepared.
(Boolean) Configure CHAP authentication for iSCSI connections. (Default: Enabled)
(Boolean) DEPRECATED: This option no longer has any affect. It is deprecated and will be removed in the next release.
(Boolean) Connect with multipath (FC only; iSCSI multipath is controlled by Nova).
(String) If operating in stretched cluster mode, specify the name of the pool in which mirrored copies are stored. For example: “pool2”
(Boolean) Storage system autoexpand parameter for volumes (True/False).
(Boolean) Storage system compression option for volumes.
(Boolean) Enable Easy Tier for volumes.
(Integer) Storage system grain size parameter for volumes (32/64/128/256)
(Integer) The I/O group in which to allocate volumes
(Boolean) Specifies that the volume not be formatted during creation.
(Integer) Storage system space-efficiency parameter for volumes (percentage).
(Integer) Storage system threshold for volume capacity warnings (percentage).
(List) Comma separated list of storage system storage pools for volumes.
(String) Specifies the name of the pool in which mirrored copy is stored. For example: “pool2”
(Boolean) Defines an optional parameter to retain an auxiliary volume in a mirror relationship upon deletion of the primary volume or moving it to a non-mirror relationship.
(String) Specifies the name of the peer pool for a HyperSwap volume. The peer pool must exist on the other site.
(Dictionary) Specifies the site information for host. One WWPN or multi-WWPNs used in the host can be specified. For example: storwize_preferred_host_site=site1:wwpn1,site2:wwpn2&wwpn3 or storwize_preferred_host_site=site1:iqn1,site2:iqn2
(Integer) Defines an optional cycle period that applies to Global Mirror relationships with a cycling mode of multi. A Global Mirror relationship using the multi cycling_mode performs a complete cycle at most once each period. The default is 300 seconds, and the valid seconds are 60-86400.
Note the following:
The authentication requires either a password (
san_password) or SSH private key (
san_private_key). One must be specified. If both are specified, the driver uses only the SSH private key.
The driver creates thin-provisioned volumes by default. The
storwize_svc_vol_rsizeflag defines the initial physical allocation percentage for thin-provisioned volumes, or if set to
-1, the driver creates full allocated volumes. More details about the available options are available in the Spectrum Virtualize family documentation.
Placement with volume types¶
The IBM Spectrum Virtualize family exposes capabilities that can be added to
extra specs of volume types, and used by the filter
scheduler to determine placement of new volumes. Make sure to prefix
these keys with
capabilities: to indicate that the scheduler should
use them. The following
extra specs are supported:
capabilities:volume_backend_name- Specify a specific back-end where the volume should be created. The back-end name is a concatenation of the name of the Spectrum Virtualize family storage system as shown in
lssystem, an underscore, and the name of the pool (mdisk group). For example:
capabilities:compression_support- Specify a back-end according to compression support. A value of
Trueshould be used to request a back-end that supports compression, and a value of
Falsewill request a back-end that does not support compression. If you do not have constraints on compression support, do not set this key. Note that specifying
Truedoes not enable compression; it only requests that the volume be placed on a back-end that supports compression. Example syntax:
Currently, the compression_enabled() API that indicates compression_license support is not fully functional. It does not work on all storage types. Additional functionalities will be added in a later release.
capabilities:easytier_support- Similar semantics as the
compression_supportkey, but for specifying according to support of the Easy Tier feature. Example syntax:
capabilities:pool_name- Specify a specific pool to create volume if only multiple pools are configured. pool_name should be one value configured in storwize_svc_volpool_name flag. Example syntax:
Configure per-volume creation options¶
Volume types can also be used to pass options to the IBM Spectrum Virtualize
family driver, which over-ride the default values set in the configuration
file. Contrary to the previous examples where the
was used to pass parameters to the Cinder scheduler, options can be
passed to the Spectrum Virtualize family driver with the
extra specs keys are supported by the Spectrum Virtualize
These keys have the same semantics as their counterparts in the
configuration file. They are set similarly; for example,
Example: Volume types¶
In the following example, we create a volume type to specify a controller that supports compression, and enable compression:
$ openstack volume type create compressed $ openstack volume type set --property capabilities:compression_support='<is> True' --property drivers:compression=True compressed
We can then create a 50GB volume using this type:
$ openstack volume create "compressed volume" --type compressed --size 50
In the following example, create a volume type that enables synchronous replication (metro mirror):
$ openstack volume type create ReplicationType $ openstack volume type set --property replication_type="<in> metro" \ --property replication_enabled='<is> True' --property volume_backend_name=svc234 ReplicationType
In the following example, we create a volume type to support stretch cluster volume or mirror volume:
$ openstack volume type create mirror_vol_type $ openstack volume type set --property volume_backend_name=svc1 \ --property drivers:mirror_pool=pool2 mirror_vol_type
Volume types can be used, for example, to provide users with different
performance levels (such as, allocating entirely on an HDD tier, using Easy Tier for an HDD-SDD mix, or allocating entirely on an SSD tier)
resiliency levels (such as, allocating volumes in pools with different RAID levels)
features (such as, enabling/disabling Real-time Compression, replication volume creation)
The Spectrum Virtualize family driver provides QOS support for storage volumes
by controlling the I/O amount. QOS is enabled by editing the
etc/cinder/cinder.conf file and setting the
There are three ways to set the Spectrum Virtualize family
parameter for storage volumes:
qos:IOThrottlingkey into a QOS specification and associate it with a volume type.
qos:IOThrottlingkey into an extra specification with a volume type.
qos:IOThrottlingkey to the storage volume metadata.
If you are changing a volume type with QOS to a new volume type without QOS, the QOS configuration settings will be removed.
Operational notes for the Spectrum Virtualize family driver¶
In the context of OpenStack block storage’s volume migration feature, the IBM Spectrum Virtualize family driver enables the storage’s virtualization technology. When migrating a volume from one pool to another, the volume will appear in the destination pool almost immediately, while the storage moves the data in the background.
To enable this feature, both pools involved in a given volume
migration must have the same values for
extent_size. If the
pools have different values for
extent_size, the data will still
be moved directly between the pools (not host-side copy), but the
operation will be synchronous.
The IBM Spectrum Virtualize family driver allows for extending a volume’s size, but only for volumes without snapshots.
Snapshots and clones¶
Snapshots are implemented using FlashCopy with no background copy (space-efficient). Volume clones (volumes created from existing volumes) are implemented with FlashCopy, but with background copy enabled. This means that volume clones are independent, full copies. While this background copy is taking place, attempting to delete or extend the source volume will result in that operation waiting for the copy to complete.
The IBM Spectrum Virtualize family driver enables you to modify volume types. When you modify volume types, you can also change these extra specs properties:
When you change the
properties, volume copies are asynchronously synchronized on the
To change the
iogrp property, IBM Spectrum Virtualize family firmware version
6.4.0 or later is required.
Configure replication in volume type¶
A volume is only replicated if the volume is created with a volume-type
that has the extra spec
replication_enabled set to
<is> True. Three
types of replication are supported now, global mirror(async), global mirror
with change volume(async) and metro mirror(sync). It can be specified by a
volume-type that has the extra spec
replication_type set to
<in> gmcv or
<in> metro. If no
is specified, global mirror will be created for replication.
replication_type set to
<in> gmcv, cycle_period_seconds can be
set as the cycling time perform global mirror relationship with multi cycling
mode. Default value is 300. Example syntax:
$ cinder type-create gmcv_type $ cinder type-key gmcv_type set replication_enabled='<is> True' \ replication_type="<in> gmcv" drivers:cycle_period_seconds=500
It is better to establish the partnership relationship between the replication source storage and the replication target storage manually on the storage back end before replication volume creation.
failover-host command is designed for the case where the primary
storage is down.
$ cinder failover-host cinder@svciscsi --backend_id target_svc_id
If a failover command has been executed and the primary storage has
been restored, it is possible to do a failback by simply specifying
default as the
$ cinder failover-host cinder@svciscsi --backend_id default
Before you perform a failback operation, synchronize the data from the replication target volume to the primary one on the storage back end manually, and do the failback only after the synchronization is done since the synchronization may take a long time. If the synchronization is not done manually, Spectrum Virtualize family block storage service driver will perform the synchronization and do the failback after the synchronization is finished.
Before creating replication group, a group-spec which key
consistent_group_replication_enabled set to
<is> True should be
set in group type. Volume type used to create group must be replication
enabled, and its
replication_type should be set either
<in> metro. The “failover_group” api allows group to be failed over
and back without failing over the entire host. Example syntax:
Create replication group
$ cinder group-type-create rep-group-type-example $ cinder group-type-key rep-group-type-example set consistent_group_replication_enabled='<is> True' $ cinder type-create type-global $ cinder type-key type-global set replication_enabled='<is> True' replication_type='<in> global' $ cinder group-create rep-group-type-example type-global --name global-group
Failover replication group
$ cinder group-failover-replication --secondary-backend-id target_svc_id group_id
Failback replication group
$ cinder group-failover-replication --secondary-backend-id default group_id
Optionally, allow-attached-volume can be used to failover the in-use volume, but fail over/back an in-use volume is not recommended. If the user does failover operation to an in-use volume, the volume status remains in-use after failover. But the in-use replication volume would change to read-only since the primary volume is changed to auxiliary side and the instance is still attached to the master volume. As a result please detach the replication volume first and attach again if user want to reuse the in-use replication volume as read-write.
A HyperSwap volume is created with a volume-type that has the extra spec
drivers:volume_topology set to
To support HyperSwap volumes, IBM Spectrum Virtualize family firmware version
7.6.0 or later is required.
Add the following to the back-end configuration to specify the host preferred
site for HyperSwap volume.
storwize_preferred_host_site = site1:20000090fa17311e&ff00000000000001, site2:20000089762sedce&ff00000000000000
storwize_preferred_host_site = site1:iqn.1993-08.org.debian:01:eac5ccc1aaa&iqn.1993-08.org.debian:01:be53b7e236be, site2:iqn.1993-08.org.debian:01:eac5ccc1bbb&iqn.1993-08.org.debian:01:abcdefg9876w
The site1 and site2 are names of the two host sites used in Spectrum Virtualize family storage systems. The WWPNs and IQNs are the connectors used for host mapping in the Spectrum Virtualize family.
$ cinder type-create hyper_type $ cinder type-key hyper_type set drivers:volume_topology=hyperswap \ drivers:peer_pool=Pool_site2
rsize is considered as
buffersize for the HyperSwap
The HyperSwap property
iogrp is selected by storage.
A group is created as a HyperSwap group with a group-type that has the
hyperswap_group_enabled set to