Nondisruptive Operations – What Does It Mean?

This blog is part of a series on Data ONTAP 8, and focuses on nondisruptive operations.  The first blog in this series was about Why Scale-Out & What’s New, and the second blog was on Unified Scale-Out – What’s Supported & Why It’s Unique.

Nondisruptive Operation (NDO) means no data outages.   As IT operations become more and more critical to business, any downtime cannot be tolerated.  Downtime causes lost business, poor customer satisfaction and a competitive weakness.  Storage infrastructures must be always on in today’s 24x7 environments.  NDO in Data ONTAP operating in Cluster-Mode is fundamental and provides the means for the storage infrastructure to remain up and serving data during hardware and software maintenance and refresh operations.

With Data ONTAP 8, you can refresh your hardware and software without losing access to your data. When it is time to refresh your hardware, you can move your data from one HA pair to another within the storage cluster nondisruptively, allowing you to retire the old hardware from the cluster. 

The ability to move your individual data volumes, known as DataMotion for Volumes, allows data to be redistributed across a cluster at any time and for any reason. Data motion is transparent and nondisruptive to NAS and SAN hosts.   This rolling-refresh approach means that you can manage, upgrade, and service your storage infrastructure nondisruptively over the life of your data—even during normal business hours.

The specific hardware and software maintenance operations that can be performed nondisruptively in a Data ONTAP 8.1 environment include upgrading from one version of Data ONTAP to another, system, disk  and switch firmware upgrades, replacing a failed controller or component within a controller (e.g. HBA, NIC) and replacing failed cables, drives, and I/O modules.

In addition, with Data ONTAP 8.1, adding storage controllers or shelves to a cluster, adding HBAs, Flash Cache, and upgrading components can be done nondisruptively, as well as, redistributing data across controllers to improve performance, moving data across controllers to rebalance capacity, and redistributing data across storage tiers within a cluster to optimize disk performance.

My next blog in this series will focus on the Storage Efficiency and Data Protection benefits of Data ONTAP 8.1 operating in Cluster-Mode.

Mike McNamara


Are you talking about cluster mode or 7 mode here. It's a bit vague, I suspect you mean both.

You seem to avoid talking about the big cluster mode feature for SMB market, which is surely moving resources between nodes with 0 downtime, while I understand in 7 mode there is up to a minutes downtime while resources are handed over.

Or am a I wrong?

Hi, talking about Cluster-Mode in the blog.