ONTAP Concepts Guide
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- Deciding whether to use the Concepts Guide
This guide describes the concepts that inform ONTAP data management software, including cluster storage, high-availability, virtualization, data protection, storage efficiency, and security. You should use this guide if you want to understand the full range of ONTAP features and benefits before you configure your storage solution. - ONTAP platforms
ONTAP data management software offers unified storage for applications that read and write data over block- or file-access protocols, in storage configurations that range from high-speed flash, to lower-priced spinning media, to cloud-based object storage. - Cluster storage
The current iteration of ONTAP was originally developed for Lenovo's scale out cluster storage architecture. This is the architecture you typically find in datacenter implementations of ONTAP. Because this implementation exercises most of ONTAP’s capabilities, it’s a good place to start in understanding the concepts that inform ONTAP technology. - High-availability pairs
Cluster nodes are configured in high-availability (HA) pairs for fault tolerance and nondisruptive operations. If a node fails or if you need to bring a node down for routine maintenance, its partner can take over its storage and continue to serve data from it. The partner gives back storage when the node is brought back on line. - Network architecture
The network architecture for an ONTAP datacenter implementation typically consists of a cluster interconnect, a management network for cluster administration, and a data network. NICs (network interface cards) provide physical ports for Ethernet connections. HBAs (host bus adapters) provide physical ports for FC connections. - Client protocols
ONTAP supports all major industry-standard client protocols: NFS, SMB/CIFS, FC, iSCSI, and NVMe/FC. - Disks and aggregates (tiers)
Aggregates (or tiers) are containers for the disks managed by a node. You can use aggregates to isolate workloads with different performance demands, to tier data with different access patterns, or to segregate data for regulatory purposes. - Volumes, qtrees, files, and LUNs
ONTAP serves data to clients and hosts from logical containers called FlexVol volumes. Because these volumes are only loosely coupled with their containing aggregate, they offer greater flexibility in managing data than traditional volumes. - Storage virtualization
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 resources. Data accessed through the SVM is not bound to a location in storage. Network access to the SVM is not bound to a physical port. - Path failover
There are important differences in how ONTAP manages path failover in NAS and SAN topologies. A NAS LIF automatically migrates to a different network port after a link failure. A SAN LIF does not migrate (unless you move it manually after the failure). Instead, multipathing technology on the host diverts traffic to a different LIF—on the same SVM, but accessing a different network port. - Load balancing
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 by reducing load (moving volumes or LUNs to different nodes as needed). - Replication
Traditionally, ONTAP replication technologies served the need for disaster recovery (DR) and data archiving. With the advent of cloud services, ONTAP replication has been adapted to data transfer between endpoints in the Lenovo data fabric. The foundation for all these uses is ONTAP Snapshot technology. - Storage efficiency
ONTAP offers a wide range of storage efficiency technologies in addition to Snapshot copies. Key technologies include thin provisioning, deduplication, compression, and FlexClone volumes, files, and LUNs. Like Snapshot copies, all are built on ONTAP's Write Anywhere File Layout (WAFL). - Security
ONTAP uses standard methods to secure client and administrator access to storage and to protect against viruses. Advanced technologies are available for encryption of data at rest and for WORM storage. - Application aware data management
Application aware data management (AppDM) enables you to describe the application that you want to deploy over ONTAP in terms of the application, rather than in storage terms. The application can be configured and ready to serve data quickly with minimal inputs by using ThinkSystem Storage Manager for DM Series and REST APIs. - Where to find additional information
You can learn more about the technologies described in this guide in Lenovo's extensive library of user documentation, technical reports, and white papers. References are organized by the section of this guide in which the technology is discussed. References are repeated if they pertain to more than one section. - Contacting Support
You can contact Support to obtain help for your issue. - Notices
Lenovo may not offer the products, services, or features discussed in this document in all countries. Consult your local Lenovo representative for information on the products and services currently available in your area.
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