NetApp Unified Driver for ONTAP with iSCSI

NetApp Unified Driver for ONTAP with iSCSI

The NetApp unified driver for ONTAP with iSCSI is a driver interface from OpenStack Cinder to NetApp ONTAP storage controllers to accomplish provisioning and management of a storage-area network (SAN) block storage entity; that is, a NetApp LUN that uses the iSCSI protocol.

To set up the NetApp ONTAP iSCSI driver for Cinder, the following stanza should be added to the Cinder configuration file (cinder.conf):

[myIscsiBackend]
volume_backend_name=myIscsiBackend
volume_driver=cinder.volume.drivers.netapp.common.NetAppDriver
netapp_server_hostname=hostname
netapp_storage_protocol=iscsi
netapp_storage_family=ontap_cluster
netapp_login=admin_username
netapp_password=admin_password
netapp_vserver=svm_name
max_over_subscription_ratio=1.0
reserved_percentage=5
use_multipath_for_image_xfer=True
  • Be sure that the value of the enabled_backends option in the [DEFAULT] stanza includes the name of the stanza you chose for the backend.

  • The value of netapp_storage_protocol MUST be set to iscsi.

Table 4.21, “Configuration options for ONTAP with iSCSI” below lists the configuration options available for the unified driver for an ONTAP deployment that uses the iSCSI storage protocol.

Option

Type

Default Value

Description

netapp_server_hostname

Required

The hostname or IP address for the storage system or proxy server. The value of this option should be the IP address of either the cluster management LIF or the SVM management LIF.

netapp_server_port

Optional

The TCP port to use for communication with the storage system or proxy server. If not specified, ONTAP drivers will use 80 for HTTP and 443 for HTTPS.

netapp_login

Required

Administrative user account name used to access the storage system or proxy server.

netapp_password

Required

Password for the administrative user account specified in the netapp_login option.

netapp_storage_protocol

Required

The storage protocol to be used. Valid options are nfs, iscsi, nvme or fc.

netapp_transport_type

Required

http

Transport protocol for communicating with the storage system or proxy server. Valid options include http and https.

netapp_size_multiplier

Optional

1.2

When creating volumes, the quantity to be multiplied to the requested OpenStack volume size to ensure enough space is available on the SVM (aka Vserver). This value is currently only used when ISCSI has been selected as the storage protocol to be used. Deprecated - use reserved_percentage instead.

netapp_vserver

Required

This option specifies the storage virtual machine (previously called a Vserver) name on the storage cluster on which provisioning of block storage volumes should occur.

netapp_storage_family

Optional

ontap_cluster

The storage family type used on the storage system; valid values are ontap_cluster, for ONTAP systems.

netapp_lun_ostype

Optional

linux

This option defines the type of operating system that will access a LUN exported from ONTAP; it is assigned to the LUN at the time it is created.

trace_flags

Optional

This option is a comma-separated list of options (valid values include method and api) that controls which trace info is written to the Cinder logs when the debug level is set to True.

netapp_api_trace_pattern

Optional

(.+)

A regular expression to limit the API tracing. This option is honored only if enabling api tracing with the trace_flags option. By default, all APIs will be traced.

netapp_lun_space_reservation

Optional

enabled

This option specifies whether space will be reserved when creating Cinder volumes on NetApp backends using the iSCSI or FC storage protocols. If this option is set to enabled, LUNs created during volume creation or volume cloning workflows will always be thick provisioned. If this option is set to disabled, LUNs created during volume creation or volume cloning workflows will always be thin provisioned. Note that this option does not affect the implementation of Cinder snapshots, where the LUN clone that represents the snapshot will always be thin provisioned. Valid options are enabled and disabled.

netapp_host_type

Optional

linux

This option defines the type of operating system for all initiators that can access a LUN. This information is used when mapping LUNs to individual hosts or groups of hosts. For a list of valid OS types, refer to the ONTAP documentation

reserved_percentage

Optional

0

This option represents the amount of total capacity of a storage pool that will be reserved and cannot be utilized for provisioning Cinder volumes.

max_over_subscription_ratio

Optional

20.0

This option is defined as a float, and specifies the amount of over-provisioning to allow when thin provisioning is being used in the storage pool. A value of 1.0 will mean that the provisioned capacity will not be able to exceed the total capacity, while larger values will result in increased levels of allowed over-provisioning.

netapp_pool_name_search_pattern

Optional

(.+)

This option is only utilized when the Cinder driver is configured to use iSCSI, NVMe or Fibre Channel. It is used to restrict provisioning to the specified FlexVol volumes. Specify the value of this option as a regular expression which will be applied to the names of FlexVol volumes from the storage backend which represent pools in Cinder. ^ (beginning of string) and $ (end of string) are implicitly wrapped around the regular expression specified before filtering.

use_multipath_for_image_xfer

Optional

If multipath has been enabled on your OpenStack hosts, then setting this option to true will permit Cinder to use multiple paths for increased bandwidth. Use of this option is also contingent upon a modification to the Nova configuration file nova.conf. The option iscsi_use_multipath = True must be added beneath the [libvirt] stanza contained within nova.conf. The inclusion of these options will not affect your OpenStack deployment in the event that multipath is not properly configured on your OpenStack hosts. Consult Recommended host settings for Linux Unified Host Utilities and Linux Unified Host Utilities Guide to configure multipath on your OpenStack hosts

filter_function

Optional

(see description)

This option may be used to override the default filter function, which prevents Cinder from placing new volumes on storage controllers that may become overutilized. The default value is “capabilities.utilization < 70”.

goodness_function

Optional

(see description)

This option may be used to override the default goodness function, which allows Cinder to place new volumes on lesser-utilized storage controllers. The default value is “100 - capabilities.utilization”.

use_chap_auth

Optional

This option is defined as a boolean, and specifies if unidirectional CHAP is enabled. Provides authenticated communication between iSCSI initiators and targets. For ONTAP the TCP port 22 (SSH) on the cluster management LIF must be open and available to set CHAP authentication credentials on the storage system.

netapp_migrate_volume_timeout

Optional

3600

This option sets time in seconds to wait for a volume Storage Assisted Migration to complete. It’s minimum value is 30 seconds.

netapp_use_legacy_client

Optional

True

Select which ONTAP client to use for retrieving and modifying data on the storage. The legacy client relies on ZAPI calls. If set to False, the new REST client is used, which runs REST calls if supported, otherwise falls back to the equivalent ZAPI call.

netapp_async_rest_timeout

Optional

60

The maximum time in seconds to wait for completing a REST asynchronous operation.

netapp_ssl_cert_path

Optional

(see description)

The path to a CA_BUNDLE file or directory with certificates of trusted CA. If set to a directory, it must have been processed using the c_rehash utility supplied with OpenSSL. If not informed, it will use the Mozilla’s carefully curated collection of Root Certificates for validating the trustworthiness of SSL certificates. Only applies when enabling the REST client.

Table 4.21. Configuration Options for ONTAP with iSCSI

Caution

If you specify an account in the netapp_login option that only has SVM administration privileges (rather than cluster administration privileges), some advanced features of the NetApp unified driver will not work and you may see warnings in the Cinder logs. See the section called “Account Permission Considerations” for more details on the required access level permissions for an SVM admin account.

Important

The option netapp_use_legacy_client can only be set to False (storage communication through REST API) when using ONTAP storage 9.11.1 or newer.