FlashCopy: Pros and Cons

To the uninitiated, IBM System Storage FlashCopy might seem like magic. But do the benefits for IBM i business continuity outweigh the hidden costs? Read on to find out.

What Is FlashCopy?

FlashCopy creates full, point-in-time copies of data that are then available for immediate read and write access, giving technicians the ability to quickly access information on different partitions. A FlashCopy of production data can shore up disaster recovery initiatives, improve production backup systems, and help in the implementation of new test environments.

In large, 24/7 IT environments, FlashCopy makes it possible to use data with a variety of applications, supporting initiatives such as software development, business integration, and data analysis. It’s a key part of any Power Systems environment.

Next, let’s take a look at some of the pros and cons of FlashCopy.

Why Should I Use FlashCopy?

The primary benefits of using FlashCopy are that it can help you be more efficient with your backups and disaster recovery. It can also bring efficiency around software development, as mentioned previously.

FlashCopy is capable of quickly establishing relationships between hundreds of volumes, writing a copy of the source volume’s contents to a target volume by mapping each one. After the connection is active, you can perform read and write I/Os on both the source and the target. You can learn more about DS8000 cascading FlashCopy design and scenarios in the IBM redbook.

FlashCopy also introduces features for addressing multiple targets with a single source or reversing the source/target relationship. Similarly, you can use a connection to Metro Mirror to create local, point-in-time copies and then copy them to remote sites.

With FlashCopy SE, it’s possible to create space-efficient DS8000 target volumes, on which physical capacity is not taken up until the data is actually written, enabling thin provisioning of targets.

With the ability to create a variety of flexible pairs and relationships, FlashCopy is suitable for many operational environments, including:

• Testing and integration setups. Developers can have rapid access to a copy of production data by using a FlashCopy, against which new applications can also be tested.
• Data backup infrastructure. FlashCopy enables backup of production data with minimal application outage time.
• Data analysis systems. Using a FlashCopy of your production data removes the need to maintain persistent data mining tasks.

What’s the Catch with FlashCopy?

Sounds great, right? So, what’s the catch with FlashCopy? It requires a storage area network (SAN), which may not be the right fit for some organizations.

Companies that only have a handful of applications or limited budgets may not need a SAN to support disaster recovery and could instead opt for software-based solutions. For shops with 24/7 service requirements and a larger portfolio of applications, a SAN supporting FlashCopy enables rapid capture and utilization of production data for many user cases.

For those running SAN, FlashCopy is a versatile solution to consider as a part of their IBM i business continuity architecture.

However, your backups could be compromised due to missing objects or other data when you use Save While Active. We recommend you watch this on-demand webinar where IBM i expert Chuck Stupca explains how FlashCopy works and how it can be combined with a SAN to provide nearly instantaneous backups and create quick test environments.