A quick guide to NetApp ONTAP’s core features

Categories: Cloud, Data Centre

It’s the breadth of features that sets ONTAP apart from all other storage operating systems so if you’re new to the technology or you just want to get up to speed with the latest updates we have brought together resources from the NetApp website, ONTAP 9 Concepts guide and our own experiences to create this blog.

Features that go beyond the core capabilities are covered in our Everything you need to know about NetApp ONTAP blog and if you would like us to add additional topics please don’t hesitate to get in touch.

The blog is broken down into the following six sections: Core Technology, Protocols, Caching & Tiering, Security, Management Tools and Platform Options.

Core Technology


One of ONTAP’s core storage technologies is known as WAFL – or, its full name – Write Anywhere File Layout. It writes updated data to new blocks using high performance full stripe writes to get around the typical RAID write penalties.


RAID (or Redundant Array of Independent Disks) is the storage industry standard method to protect against drive reliability or failure related issues. The most common type of RAID protection used with ONTAP based systems is RAID-DP (which uses two parity drives to add resilience to the disk group)  – and more recently with the release of >4TB capacity orientated hard disks the recommendation is to utilise RAID-TEC (that uses three parity disks). These mechanisms – plus the use of spare disks – ensure that each system has the ability to handle any hard disk issues in a timely, non-disruptive manner.

Storage Virtual Machines (SVMs)

You use storage virtual machines (SVMs) to serve data to clients and hosts. Like a virtual machine running on a hypervisor, an SVM is a logical entity that abstracts physical (drive/network) resources. SVMs give storage administrators the ability to segregate data from different departments and provide multi-tenancy.


ONTAP provides clustering features that can be utilised for capacity and performance scaling as well as non-disruptive operations. Typically, each dual-controller hardware appliance is comprised of two nodes that work together in a cluster as a high-availability pair (HA Pair).

This concept can be extended to additional appliances (HA Pairs) to provide either additional capacity, performance or both.

This makes hardware refreshes a breeze as once the new appliance is added to the cluster and basic connectivity tests completed you can immediately cut over production workloads live without disruption.

For software-defined and public cloud deployments you can also take advantage of multi-node HA features.

Quality of Service (QoS)

Performance of workloads begins to be affected by latency when the amount of work on a node exceeds the available resources. You can manage an overloaded node by increasing the available resources (upgrading disks or CPU), or by reducing load (moving volumes or LUNs to different nodes as needed). You can also use ONTAP storage quality of service (QoS) to guarantee that performance of critical workloads is not degraded by competing workloads.

Adaptive QoS automatically scales the policy group value to workload size, maintaining the ratio of IOPS to TBs/GBs as the size of the workload changes. That’s a significant advantage when you are managing hundreds or thousands of workloads in a large deployment.

Thin Provisioning

A thin-provisioned volume or LUN is one for which storage is not reserved in advance. Instead, storage is allocated dynamically, as it is needed. Free space is released back to the storage system when data in the volume or LUN is deleted.

A VMware vSphere NFS datastore can be provided from a thinly provisioned volume thereby giving it the possibility to be grown OR shrunk on the fly without downtime.



ONTAP supports all major industry-standard protocols: NFS, SMB/CIFS, FC, FCoE, iSCSI, S3 (Object) and NVMe/FC. The configurations of each protocol are managed at the SVM level for convenience and security purposes.

Here is a breakdown of each protocol’s core features from the ONTAP 9 Concepts Guide.


NFS is the traditional file access protocol for UNIX and Linux systems. Clients can access files in ONTAP volumes using the NFSv3, NFSv4, NFSv4.1, and pNFS protocols. You can control file access using UNIX-style permissions, NTFS-style permissions, or a mix of both. NFS is extremely popular with VMware vSphere users for virtual machine storage as each NFS datastore can be quickly provisioned, grown and shrunk.


SMB/CIFS is the traditional file access protocol for Windows systems. Clients can access files in ONTAP volumes using the SMB 2.0, SMB 2.1, SMB 3.0, and SMB 3.1.1 protocols. Just like with NFS, a mix of permission styles are supported.

SMB 1.0 is available but disabled by default in ONTAP 9.3 and later releases.


Fibre Channel is the original networked block protocol. Instead of files, a block protocol presents an entire virtual disk to a client. The traditional FC protocol uses a dedicated FC network with specialised FC SAN switches, and requires the client computer to have FC network interfaces (typically known as HBAs).

A LUN represents the virtual disk, and one or more LUNs are stored in an ONTAP volume. The same LUN can be accessed through the FC, FCoE, and iSCSI protocols, but multiple clients can only access the same LUN if they are part of a cluster which prevents write collisions.


FCoE is basically the same protocol as FC, but uses a datacenter-grade Ethernet network in place of the traditional FC transport. The client still requires an FCoE-specific network interface.


iSCSI is a block protocol that can run on standard Ethernet networks. Most client operating systems offer a software initiator that runs over a standard Ethernet port. iSCSI is a good choice when you need a block protocol for a particular application, but do not have dedicated FC networking available.


One of the latest additions to ONTAP is the support for the S3 object storage protocol with the data stored within FlexGroup volumes. There are three primary use cases:

  • ONTAP systems using S3 as a remote FabricPool tier
  • ONTAP systems using S3 as a local FabricPool tier
  • Serving S3 client applications

The newest block protocol, NVMe/FC, is specifically designed to work with flash-based storage. It offers scalable sessions, a significant reduction in latency, and an increase in parallelism, making it well suited to low-latency and high-throughput applications such as in-memory databases and analytics.

Caching & Tiering

Flash Cache

Flash Cache is installed on each controller and it improves the performance of all aggregates. In particular, it is designed to improve random-read performance rather than sequential or write I/Os.

Flash Pool

Flash Pool is a caching technology. It groups together spinning disks with a group of cache SSD drives. The caching algorithms used can be set (or disabled) on a per-volume basis and there are built-in workload analysis tools within ONTAP to recommend the optimum amount of SSD cache for an existing hard disk based aggregate.


FabricPool is a data tiering technology that aims to increase the efficiency of your data storage by only keeping the hottest data on high performance local storage tiers. FabricPool ‘cold’ data can then be tiered to public cloud or ONTAP S3 hosted buckets for longer term storage.


FlexCache is a remote caching solution for SMB or NFS that simplifies file distribution, reduces WAN latency, and lowers WAN bandwidth costs. It enables distributed product development across multiple sites, as well as branch office access to corporate datasets.



SnapLock is a high-performance compliance solution for organisations that use WORM storage to retain files in unmodified form for regulatory and governance purposes. A single license entitles you to use SnapLock in strict Compliance mode, to satisfy external mandates and a looser Enterprise mode, to meet internally mandated regulations for the protection of digital assets.


ONTAP offers both software and hardware-based encryption technologies to ensure that data at rest cannot be read if the storage medium is repurposed, returned, misplaced, or stolen. Typically hardware level encryption is for the whole system whereas software level encryption can be applied on a per-volume basis only for the data that requires it.

Secure Purge

Secure Purge cryptographically shreds files stored on an Encrypted NetApp Volume, allowing you to non-disruptively “scrub” data on these volumes, ensuring that data cannot be recovered from the physical media and thereby ensuring that data leaks will not inadvertently take place should retired media be interrogated by a third-party.


The FPolicy framework manages activities on the cluster and sends notifications to external servers which process them and return results (e.g. allow/disallow a file to be created). Typical applications include anti-virus/ransomware scanners, auditing services and more.

Management Tools

System Manager

System Manager is an HTML5 web-based interface that enables you to manage storage systems and their storage objects (such as disks, volumes, and aggregates). It runs on-board the storage platform to perform common storage-system management tasks such as setting up remote protection or creating new network objects and file shares.

Active IQ

Active IQ is a tool to proactively monitor and optimise your NetApp environment. It is hosted in the cloud and accessible via web browser or mobile application.

Typical uses are:

  • Identify and remediate system health risks that can cause downtime
  • Uncover systems reaching performance or capacity limits
  • Identify and remediate security risks
  • Plan system software upgrades

Active IQ Unified Manager

Active IQ Unified Manager enables you to monitor and manage the health and performance of your ONTAP storage systems from a single interface. It is typically deployed as virtual appliance on to a VMware environment (support for other platforms also available). It is useful as an on-premise tool for multi-system monitoring, performance analysis and security posture checking.

VMware integration

VMware and NetApp are Global Partners that provide integrated solutions for virtual environments. One of the most well-known components – ONTAP tools for VMware vSphere (also known by its previous name, Virtual Storage Console) provides best practice settings, storage provisioning, re-sizing and data protection features for the SAN and NAS volumes hosted on ONTAP systems directly from VMware vCenter.


XCP is a free client software tool that enables fast and reliable any-to-ONTAP and ONTAP-to-ONTAP file migrations. The latest incarnation of the software also has an analytics component that provides deep visibility into the file system.

Platform Options


All Flash FAS is a powerful scale-out platform built for virtualised environments, combining low-latency performance with best-in-class data management, built-in efficiencies, integrated data protection, multiprotocol support (NAS, SAN and Object), and nondisruptive operations.


All SAN Array builds on the AFF platform to deliver continuous SAN availability for enterprises that run missioncritical applications. These systems provide uninterrupted access to data during a planned or unplanned storage failovers and deliver streamlined implementation, configuration, and management through a solution that’s dedicated only to running tier 1 SAN workloads. NAS and Object protocols are not supported.


FAS runs the same ONTAP operating system as the AFF platform but with the ability to support a hard disk only or hybrid hard disk and flash deployment option. It is a multi-protocol NAS, SAN and Object platform that can form part of a scale-out cluster with other FAS and AFF nodes.

ONTAP Select

ONTAP Select is a software-defined storage appliance that you can deploy on a variety of commodity hardware servers running the VMware ESXi and KVM hypervisors. ONTAP Select converts a server’s internal disk drive resources into an agile, flexible storage system with the features of ONTAP. Ideal for edge deployments that can easily then be replicated to a central location.

Cloud Volumes ONTAP

Cloud Volumes ONTAP allows you to take the software-defined storage approach from on-premise and run it in the public cloud. There are multiple configuration options available so you can design, manage and protect your virtual storage appliances as you would a traditional ONTAP storage system. Amazon Web Services (AWS), Microsoft Azure and Google Cloud Platform (GCP) are all supported.

ONTAP services for AWS, Google Cloud and Azure

NetApp Cloud Volumes Service is a fully managed cloud storage solution that is available for Amazon Web Services (AWS) and Google Cloud Platform (GCP). For Microsoft Azure, NetApp and Microsoft have created a first-party service called Azure NetApp Files that offers a high-performance file-service environment for the Microsoft Azure cloud. These services support NFS v3 and SMB, can grow to 100TB, and run file shares at peak performance while providing the best data protection and security in an organisation’s preferred cloud provider.

Tags: , , , ,
Flash Optimised, Cloud Integrated & Multi-Protocol – the table stakes of modern storage
12 key data strategies for 2021