Migrations to z/OS 1.10 go more smoothly than with previous versions, but they certainly aren't free of problems, said users at the Share mainframe user group conference.
Released six months ago, the new version includes features to extend address volumes up to 223 GB, configure disk-replication services more intuitively and offload more workloads to specialty mainframe processors for data and Java applications. But not everyone upgrades to the newest operating system because of the brand-new features. Some do it mainly to keep up with maintenance.
"Primarily when we upgrade, it's so that when we get new hardware, the software is as up to date as possible," said Alan Field, a mainframe programmer for SuperValu Inc., the third-largest grocery retailer in the country.
Field relayed the story of a former coworker who was upgrading from an IBM 3350 storage device to an IBM 3380. Maintenance wasn't up to date, so it took three months to install thousands of patches -- called program temporary fixes (PTFs) -- before the upgrade was complete.
At SuperValu, upgrading to z/OS 1.10 takes place across 20 logical partitions (LPARs) in four mainframes at two data centers in Minnesota and Idaho. The company placed its order for z/OS 1.10 when the release became generally available in September and plans to start running production on the new OS in May. SuperValu lengthened the timeline because of a lack of cooperation to test within the company and because 1.10 restricted the company's ability to do initial program loads (IPLs) only once a month, Field said. With z/OS 1.8, the current production OS, SuperValu could do IPLs every week.
The download for z/OS 1.10 -- done using ShopzSeries -- was smoother than with 1.8, Field said. SuperValu dealt with some issues, however:
- Getting the interface to lay out in the right way;
- Had to re-initialize the storage device and restart the loading a couple of times, at both sites;
- Discovering that the z/OS System Display and Search Facility (SDSF) is now delivered in four libraries, primarily because it now supports JES2 and JES3.
Micheline Bissell, a system engineer for insurance company Aetna, took part in the beta program for z/OS 1.10, the IBM Early Support Program (ESP). The program was old hat for Aetna, which has participated in ESPs starting with z/OS 1.6. The company plans to roll out 1.10 in production to its multiple sysplexes in two data centers starting in March and finishing in early June.
Being part of an ESP means finding bugs, and Bissell considers that a responsibility.
"Our job is to find and flush out bugs in the code so that IBM can deliver a robust product at [general availability]," she said.
Much of Aetna's focus was on the independent software vendors (ISVs) that had to roll out updates to their own software to work with the new version of z/OS. Aetna has more than 100 ISV products on its mainframes, so sorting through all of them was a grind, Bissell said. They encountered issues with CA (its biggest third-party software vendor), Innovation Data Processing, OpenTech Systems Inc. and ISVs, but all these problems were eventually fixed, she said.
"We have more than 100 ISVs, and about 20 different products needed fixes," she said. "Most of them were ahead of us, and they notified us. So we didn't really run into a lot of ISV issues. All in all, we were happy."