HelpSystems Blog

IASPs: What They Are and Why You Need Them on IBM i

IBM i expert Chuck Stupca and Chuck Losinski recently presented an engaging webinar about the unique characteristics of IASPs and how application data can be seamlessly migrated to optimize system processes.

“As PowerHA grows in popularity, so do independent auxiliary storage pools (IASPs),” the presenters explained. “IASPs are the key to high availability for critical objects on the IBM i, but many users still don’t understand how to use IASPs to their advantage. Some believe they are difficult to deploy, others are at a loss for why they’d use IASPs in the first place.”



Explaining IASPs

The webinar included valuable information about independent auxiliary storage pool technology, which is a collection of disk units that can be brought online or taken offline and kept independent of the rest of the data on a storage system that is connected to IBM i. Stupca explained that IASPs provide a way to mitigate risk of disk failure by designating part of the disk unit for various object storage. Independent ASPs are not automatically a part of address space.

Stupca outlined the different types of ASPs: basic and independent. Basic ASPs are numbers 2 through 32 and are linked to the system ASP. They cannot be independently varied on or off and are primarily used to isolate journal receivers from the data in the system ASP. Independent ASPs can be independently varied on and off and switched between systems. When created, IASPs are identified by device description and by number, ranging from 33 through 255. The three types of IASPs include UDFS, primary, and secondary. UDFS can only hold IFS objects, while primary and secondary can also contain library objects. Primary IASPs can be accessed by SETASPGRP, and secondary IASPs are linked to a primary.

Benefits of IASPs

Stupca also outlined how ASPs can provide a foundation for long-term, scalable HA/DR. IASPs can potentially provide improved uptime by enabling administrators to leave non-critical IASPs offline and free up storage space. IASPs also boost security through path encryption and offer consolidation perks including lower costs from the reduction of software licensing fees and the number of operating system upgrades necessary. IASPs can be used for a variety of purposes, and Stupca noted that they’re commonly used to isolate data associated with specific applications as well as to enable a more granular approach to work management.

At HelpSystems we see more and more customers using IASP technology exclusively with PowerHA. PowerHA gives you the ability to move large amounts of data between two physical servers in seconds and, in fact, you cannot use PowerHA without an IASP.

In response to the growing demand for applications with the ability to move with other IASP applications in high availability environments, many of our IBM i systems management solutions—including Robot Schedule and Robot Console—work in the IASP. You can install or upgrade directly into an IASP alongside your IASP-aware software, as well as move with your IASP. In the case of Robot Console, you can also take advantage of a second installation in *SYSBAS in order to continue monitoring QSYSOPR and other resources while the IASP is offline.

The IASP Experts

In addition to Chuck Stupca, HelpSystems has also connected with IBM's Steve Finnes, Product Offering Manager for Power HA/DR and a leading expert on IASP technology. Finnes confirms that it’s past time we “get to know it, understand it, and not be afraid of it.” You can read our interview with Steve Finnes here.

If you have questions about incorporating IASP into your IT plans or want information on which HelpSystems products supports IASP, schedule a Tech Update with our experts. Tell us what's on your mind and we'll point you in the right direction.