IBM Puts The Finishing Touches On PowerHA For IBM i 7.5
August 15, 2022 Alex Woodie
If you have been waiting to use the new release of PowerHA SystemMirror for IBM i 7.5, then we have good news for you: IBM has finally completed the paperwork necessary to enable customers to actually get it.
Unless you have a soft spot in your heart for IBM product IDs and feature codes (we know you’re out there), the August 9 software announcement doesn’t have a whole lot of actionable information. IBM says that it has updated the product “with the necessary product IDs and feature codes to complete the required ordering and upgrade structure,” which is IBM-speak for “we’re open for business.” The planned availability date is August 23.
IBM originally announced the new release of PowerHA SystemMirror for IBM i 7.5 back on May 3, which astute readers will note was announcement day for IBM i 7.5 and 7.4 TR6. That release (which was technically PowerHA version 5.0.1) contained several compelling new features, and was slated to ship June 24. (It’s unclear if it became available on that day, or if the lack of product IDs and feature codes meant the availability was pushed back to next Tuesday.)
In any event, the new release of PowerHA is (or soon will be) ready for use by IBM i customers. There were three main new features delivered with PowerHA version 5.0.1, the version that runs on IBM i 7.5; two of these features are also available on other versions of PowerHA designed to run on older versions of the i OS, including PowerHA version 4.6.1 (for IBM i 7.4) and PowerHA version 3.8 (for IBM i 7.3).
One of the biggest new features is the addition of compression for geographic mirroring, which will reduce the amount of data sent across the network. Brian Nordland, the HelpSystems product manager who oversees PowerHA on behalf of IBM, explains the significance of this new feature:
“Geographic mirroring performs disk-level replication. This means that all changes on disk in an Independent Auxiliary Storage Pool (IASP) are replicated over the TCP/IP network to the target system. When PowerHA performs a synchronization, either for the initial synchronization, after an unplanned failure, or when resuming from a suspend operation, PowerHA replicates data over the TCP/IP network.”
“With this enhancement, PowerHA can now compress geographic mirroring data during resynchronization reducing the data transfer required,” Nordland writes in a PowerHA product wiki article dated May 19. “In addition, on Power10 systems, PowerHA uses the on-chip NX GZIP accelerator if the NX feature is enabled, providing hardware accelerated compression.” This enhancement would be available on June 24 for both PowerHA 7.5 and 7.4, he added.
Another new feature is a reduction in the time required to perform CRG switchovers for selected configurations. Nordland explains:
“Previously, when performing a switchover of a device Cluster Resource Group (CRG), the job queue specified in the job description for the user performing the switchover was used to vary off and on the IASP. This may result in the switchover taking longer than expected. For example, if the job queue is held or only allows a specific number of active job (sic) at a time, the switchover may be held up for a long time. Previously, PowerHA included switchover progress monitoring that visually indicates a job submitted but not yet running to help identify these situations.”
“PowerHA has been enhanced so that planned switchovers or unplanned failovers will always use the QSYSNOMAX job queue for iASP vary on and off operations regardless of the user initiating the operation,” he continues. “This reduces the chance of a held job queue or hitting the restriction on the maximum number of active jobs in the subsystem, reducing the time required to perform the CRG switchover.” This new feature would be available for 5.0.1, 4.6.1, and 3.8, he said.
Lastly, IBM has simplified the product packaging with this release (although it still features an abundance of product IDs and feature codes, you will be happy to know). IBM has reduced the number of PowerHA editions down to one, which contains all of the functionality. The catch is this all-in-one-version is only available with 5.0.1, which only runs on IBM i 7.5.
But wait, there’s more! (There always is, which is a good thing.) The HelpSystems code cobblers have been hard at work since May, and in June, they released new updates to the three currently supported versions of PowerHA, including PowerHA versions 5.1.2, 4.7.2, and 3.9. The big new feature is the addition of Spectrum Virtualize FlashCopy automation that should simplify the mirroring process. Nordland explains the new feature in a June 24 article on the PowerHA wiki:
“The Spectrum Virtualize (SVC) based FlashCopy automation integrated into PowerHA now includes additional automation at the target system of Geographic Mirroring, eliminating the need to manually suspend or detach the geographic mirroring replication as part of the FlashCopy process,” he writes.
PTFs are available for the new releases. You can find more information on the new features at HelpSystems PowerHA product wiki page.