I used to work at a place that did this. The only issue we ran into was memory was HELLA expensive on the z series boxes. It was to the point that it was cheaper to buy an hp server with 1TiB ram than get 16g of ram from the zaaps.
That and getting software to run on it was almost impossible. In the end we ended up moving everything to HP servers for a fraction of the cost.
When deployments like this happen, where does the z series box then go? Back to IBM (because it was on lease?) Is the z series modular enough that it's easy for ibm to reconfigure to lease to someone else?
If it was a lease through something like IBM Global Services they will take it back and possibly redeploy it. Otherwise, they can kind of get lost in the noise, either ending up at auction or straight to an edisposal service. They are usually parted out at that point to sell spare parts, because the licensing makes it nearly impossible to use one of these w/o involving and paying IBM, usually monthly. Otherwise they are crushed for precious metal recovery. Kind of sad ends for such works of art.
The Linux dichotomy IBM created is pretty stupid. I don't know why you'd want to run a tire fire on such expensive HW, sure maybe utility VMs, but not as the raison d'etat. Instead they should be a lot more willing to provide cheap z/VM, z/OS, z/TPF licenses for smaller shops to build up an ISV, admin, and porting community. But they charge thousands of dollars for an emulator when Hercules is freely available and ADCD is quite restricted.
I recently bought an older one for the cost of a soda https://twitter.com/kevinbowling1/status/685240077161598976. I would warn against doing this for a number of reasons, namely FICON storage and licensing, but if you are determined it is a lot of fun.
Thats cool, your lucky with the z800, most of the other mainframes have "exotic" (aka 3 phase 277/480) power requirements. We had to pull power in our existing computer lab to run our MF. So, while its possible to order most mainframe equipment for single phase 208, it doesn't appear to be the default choice for the kinds of places that buy mainframes.
I settled for hercules at home, hell of a lot easier to manage, and is pretty fast given that its a fairly naive emulator (aka no JIT/tracing/etc). I think if the turbo hercules guys (or someone else) added a decent JIT, and solved the licensing problem IBM would be in a world of hurt. Although, maybe not, the few remaining customers aren't the kind to run their bank/airline/etc on a 10k piece of hardware and an open source emulator. Of course, I've been wondering for a few years what percentage of machines are being sold to development shops to support the limited number of real customers. That is why we purchased ours, to support real customers, not to run any actual work on it. Of course I've also heard that most of the business class machines are sold with tiny capacities, because they are simply hot fail-over targets. The assumption is that if something goes wrong at the primary site, someone calls up IBM and gets them to boost the capacity on the idle machine as the workload is shifting over.
Yeah IBM really created a false dichotomy. Production users want the mainframe architecture and reliability. Developers are fine with emulation and create demand.
I've got to imagine they are barely breaking even on a minimal config baby class system. The yield on an MCM has to be minimal. You can find videos of how labor intensive the build of a frame is, let alone the engineering. I wouldn't even be surprised if they were loss leaders.
And that begs the question, why not grow the user base with aggressive placement, training, and development. Another $1 billion investment in Linux has no appreciable affect to most mainframe users, and no way there is an ROI. Imagine that injection on this small, loyal platform of users.
Yep, either IBM says ok thanks we'll move this hardware to somewhere else. Or the other odd thing about mainframes, they ship them out fully loaded, and make it so they can turn on the hardware you want if you need it.
Yeah, it is a weird environment. The i/o on them is nice though, but everything else is so wackadoo I never want to touch it.
But from what the mainframe guys at work told me, hardware between 2 z boxes are pretty much the same and it's kind of licensed by load usage or components usage.
So if you want to downgrade or upgrade memory/CPUs/etc. (to a certain degree), it's just a matter of having an IBM tech to enter the right license in the console.
That and getting software to run on it was almost impossible. In the end we ended up moving everything to HP servers for a fraction of the cost.