On an ASA r2 system, ONTAP software is streamlined to provide support for essential SAN functionality while limiting the visibility and availability of non-SAN related features and functions. For example, System Manager running on an ASA r2 system does not display options to create home directories for NAS clients. This streamlined version of ONTAP is identified as the ASA r2 personality. ONTAP running on ASA systems is identified as the ASA ONTAP personality. ONTAP running on AFF and FAS ONTAP systems is identified as the unified ONTAP personality. The differences between ONTAP personalities are referenced in the ONTAP command reference (man pages), REST API specification, and EMS messages where applicable.

You can verify the personality of your ONTAP storage from System Manager or from the ONTAP CLI.

For ASA r2 systems, the personality is ASA r2 and the status of is-disaggregated is true.

The personality of your ONTAP storage system cannot be changed.

ASA r2 systems use a simplified storage layer that is different from the storage layer used by FAS, AFF, and ASA systems.

The storage layer for FAS, AFF, and ASA systems use aggregates as the base unit of storage. An aggregate owns a specific set of the disks available in a storage system. The aggregate allocates space on the disks it owns to volumes for LUNs and namespaces. With these systems, ONTAP users can create and modify aggregates, volumes, LUNs and namespaces.

Instead of aggregates, the storage layer in ASA r2 systems uses storage availability zones. A storage availability zone is a common pool of storage available to both nodes of a single HA pair. Both nodes in the HA pair have access to all available disks in their shared storage availability zone. For example, in a 2-node ASA r2 system ONTAP cluster, there is one storage availability zone, accessible by both nodes in the cluster. In a 4-node ASA r2 system ONTAP cluster, there are two storage availability zones. Each HA pair in the cluster has access to one of the storage availability zones.

When a storage unit (based on either a LUN or an NVMe namespace) is created, ONTAP automatically creates a volume in the appropriate storage availability zone to house the storage unit. The newly created volume is automatically placed within the storage availability zone for optimal performance and balanced capacity utilization. Depending upon your version of ONTAP, ASA r2 systems also support automatic rebalancing of storage units across the storage availability zone and automatic rebalancing of workloads between the nodes in an HA pair.

ASA r2 systems differ from FAS, AFF, and ASA systems in the following ways:

Because of this automated and simplified approach to storage management, certain System Manager options, ONTAP commands, and REST API endpoints are not available or have limited usage on an ASA r2 system. For example, because volume creation and management is automated for ASA r2 systems, the Volumes menu does not appear in System Manager and the volume create command is not supported. Learn more about unsupported ASA r2 commands.

The major differences between ASA r2 systems and FAS, AFF, and ASA systems relevant to the ONTAP command line interface (CLI) and REST API are described below.

New clusters automatically contain a default data SVM with the SAN protocols enabled. IP data LIFs support iSCSI and NVMe/TCP protocols and use the default-data-blocks service policy by default.

Creating a storage unit (LUN or namespace) automatically creates a volume from the storage availability zone. This results in a simplified and common namespace. Deleting a storage unit automatically deletes the associated volume.

Storage units are always thinly provisioned on ASA r2 storage systems. Thick provisioning is not supported.

Temperature-sensitive storage efficiency is not applied on ASA r2 systems. On ASA r2 systems, compression is not based on hot (frequently accessed) data or cold (infrequently accessed) data. Compression begins without waiting for data to become cold.