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Obtaining Mainframe Experience w/o a Mainframe?
Nice2Cats asks: "So I'm reading all over about how companies are desperate for people who know how to work mainframes, especially now that IBM is shipping them with Linux. But how -- short of a course with Big Blue or some other exercise in expensive formal education -- can I acquire even the most basic information or experience with big iron? There doesn't seem to be many tutorials or introductions online; what would be nice, but I can't seem to find either, would be a simulator that would run on a PC. All I want to know is if I like enough to be seriously interested."
You wish to simulate a mainframe on a home pc do you? Good luck with that. I think you just might take a severe hit in performance compared to a real mainframe.
yet excellent page on just this topic. :)
HERE
Hope this helps!
For every annoying gentoo user, are three even more annoying anti-gentoo crybabies. Take Yosh from #Gimp for example.
Hercules was created by Roger Bowler and is maintained by Jay Maynard. Jan Jaeger designed and implemented many of the advanced features of Hercules, including dynamic reconfiguration, integrated console, interpretive execution and z/Architecture support.
"Flyin' in just a sweet place,
Never been known to fail..."
At least, that's the theory. After doing a fair amount of mainframe work, mostly with VM/CMS, I got to the point where the extreme weirdness of the environment was kind of cool in a retro sort of way, and I began to get a sense of how it all fit together. But this is not something you're going to pick up from a tutorial on the Internet.
:'}
Basically, if you want to do mainframe stuff, you should find someone to hire you who needs some work done and doesn't mind paying you to learn, and then *don't assume you know what you're doing*. Even the way terminals and serial ports work is different. Many of the basic assumptions about how operating environments work are different on mainframes. CPU time is not free - if you accidentally run a spin loop, it can cost thousands of dollars very quickly.
It's a very weird environment...
It wouldn't surprise me if there were a 370 emulator out there, but where are you going to get the software to run on it?
AS/400's come up on ebay all the time. Maybe a little small for your definition of a mainframe, but they will fit in your apartment.
"Eve of Destruction", it's not just for old hippies anymore...
The same way as everyone else got mainframe experience in the old days: Entry Level Position.
7 November 2006: The day Americans realized corruption and incompetence weren't addressing 11 September 2001
Not just for Breakfast anymore...
IBM has pretty decent documentation on their stuff, at least the AS/400 docs were good.
Go here for the zSeries and S390 docs.
"From my cold, dead hands you damn, dirty apes!" - CH
I'vebrought up Hercules at home and it does a good job at the HARDWARE level. the real issue is that of getting an O/S that you CAN run.
Older versions of MVS (ie MVT) are available, as are older versions of VM. However, these run in 370 mode, not in ESA or Z mode.
I'm not sure about what Linux versions would run on this emulator.
It is though still a good means of gaining some familiarity with the environment.
If you could simulate a mainframe on a PC, do you really think mainframes would be so expensive?
(It's a JOKE)
j00 mu57 h4x0r 73h g1b50n, 4n|) |)0wn104d "garbage"
Didn't we already have this discussion awhile back?
Does it do it at a hardware level, like BOCHS or VMWware?
Do companies do training, anymore? Or, do they expect everyone to learn everything of relevance on their own time with their own resources or at the expense of a prior employer? Or, are there such a surplus of qualified canidates milling about that even thinking about making a horizontal career change is laughable?
For example, while the author of the article above wanting to learn mainframes is cute, would any company give a damn if he already has several years experience but didn't already learn the ins and outs of mainframes hands-on in a former employer's "enterprise" environment?
It just seems that ground-floor opportunities are a myth. Ugh.
Vote in November. You won't regret it.
Depending on what you consider a mainframe, there's always SIMH, a rather nice emulator for PDPs, PEs, and a number of others. There are some other free emulators out there, but I know nothing aout them. I've brought up a PDP-8 and PDP-11 under SimH before.
You can see how UNIX people think by looking at shell, sed, awk, and perl scripts. Why not look for MVS/JCL, RPG (aka Rotten Piles of Garbage), Cobol tutorials and examples. You may also come across the problems people were trying to find solutions for. FWIW, my impression is that mainfraim world is *much* more regimented than the most locked down UNIX box.
I suggest poking around http://99-bottles-of-beer.ls-la.net/, even has s/390 and s/370 assembler.
I thought they were all in India these days.
Software thinks you have a 360 or 390 or whatever under it.
"Flyin' in just a sweet place,
Never been known to fail..."
Just hack into one, and 'borrow' some time on it.
Jesus was all right but his disciples were thick and ordinary. -John Lennon
Have you tried this? You can test drive a bunch of different systems and OSs.
So yes, Hercules emulates all the hardware including the CPU. Very radically different machine.
Disclaimer: I in no way know anything about any copyright or license violations and hardly speak for myself, much less my tiny tiny offshore company with absolutely no attachable assets.
I happen to be typing on one of these babies right now. My thinkpad is running Redhat 8 as the host OS, with the FLEX-ES emulator that lets me run zOS or z series Linux (Suse in my case). The emulator has dongles and is pretty touchy about the hardware as well, so odds are you will pick up a xSeries machine or a T30 Thinkpad if you want to do a mainframe on the cheap.
(Cheap being a relative thing when you are talking about mainframe costs, btw...)
+++ UGUCAUCGUAUUUCU
My dad has been a mainframe guy for years, and out of work for almost 2 now. Nobody will look at him because he only has a 2 year tech school degree. So they may want mainframe people, but don't think they are desperite enough to be flexable on their requirements.
All technology has two humps. On the first hump, you make a lot of money because the technology is hot. For example, .net. Then because the technology pays alot of money, a lot of people get into it and the pay goes down because the employee supply goes up.
The technology becomes main stream and doesn't pay very much. Then, after a while, people start getting out of that technology. They retire. They become Pointy Hair Bosses. They get out of it. So the supply of knowledgeable employees goe down, and the pay goes back up. But the technology is dieing. It's days are numbered.
For the most part, mainframes are on the second technology hump. You only get paid alot because old foggies are the only ones who know anything about. Basically, it's a waste of time to pursue mainframe knwoledge, because it's pay heighth is fairly limited.
Solaris on the other hand is on the top of first hump. You can make a career out of knowing it. Linx on Micros is an up and comer on the hump. Windows is on the first hump. Mainframes are dieing.. just like cobol. Don't waste your time.
This isn't the sig you are looking for... Carry on...
Perhaps counterproductive for your carrier, but I've ran into an impressive array of Mainframe and Minicomputers in the Navy, particularly in the Intelligence/Cryptology field. At the tender age of 19, I was assigned to administer a PDP11/70 based broadcast server. I was given a full bookshelf of manuals, and told "go figure this out..". This was 1994. I still have the faceplate from that beast from when we decommissioned it. Next in my parade of obsolete equipment was an AT&T 3B2/600 running SVR4. Not exactly "Mainframe" material, but old and cranky regardless. Then a VAX server monster running VMS. In a big ugly building in Hawaii, all sorts of ancient IBM, DEC, SGI, Sun, Hp and even Cray are still alive and well. Typically the Navy assigns one SYSADM to a big mainframe, issues them a pager, and wishes them good luck. You'd be amazed how quickly you learn something when you know that you are the only one available (with the proper security clearance) to fix something, and your not getting to sleep until it's done. I've found that the factory manuals are pretty good. Hard to read and dry as a bone, but the important stuff is all there. I haven't checked eBay, but that might be a place to start. Often, defense contractors hire technically inclined individuals for part time employment. You'd be amazed at the kind of hardware you can get your hands on with that sort of job. Getting the required security clearance is the only real hurdle.
This is probably not considered a mainframe, but does anyone know how to train with OS/400 and z/OS ?
A lot of companies are looking for people with AS/400 knowledge. But none is willing to pay any initial training ("because it would be cheaper to get a support contract with IBM" I was told once).
So they are looking for people who already know about AS/400.
But AS/400 is not something we usually learn at CS school. I've looked at AS/400 learning sessions at IBM's and at various learning centers and prices are way too high for an individual, even to learn the basics.
So I'm desperate : is there any way to get experience on those machines?
Any emulator, maybe?
{{.sig}}
If companies are really desperate for people with mainframe skills, then they will have to consider on-the-job training. However this doesn't necessarily help you. If you don't have mainframe skills, you will have to beat all of the other job applicants without mainframe skills. However, if you demonstrate commitment by attempting to self-educate on mainframe technology, this could make you stand out from the crowd in the eyes of a prospective employer.
When a company migrates away from IBM proprietary operating systems to Linux, this will tend to reduce their dependence on the diminishing pool of people with "mainframe skills". Skills in developing software and/or using Linux are applicable across a wide range of hardware platform. If anything, Linux on IBM would be a reason to invest personal effort in acquiring these skills.
Simply go 88 MPH and have enough plutonium to get back!
"So I'm reading all over about how companies are desperate for people who know how to work with chicks, especially now that they are so common down in the Mall. But how -- short of a course with a mate's girlfriend or some other exercise in expensive sex for hire -- can I acquire even the most basic information or experience with big tits? There doesn't seem to be many tutorials or introductions online; what would be nice, but I can't seem to find either, would be a simulator that would run on a PC. All I want to know is if I like enough to be seriously interested."
Specialist Mac support for creative pros, Melbourne
There's a free mainframe emulator, but the available operating systems for it are either Linux-based or obsolete IBM operating systems. IBM still charges very high prices for their current mainframe operating systems.
It's a pure interpreter written in C, and thus slow; emulation costs you about two orders of magnitude in performance. But that gives you the performance of an entry-level IBM mainframe circa 1998 or so.
There's a commercial emulator called FLEX-ES, but if you have to ask how much it costs, you can't afford it. It's being sold to companies who are replacing old IBM mainframes with an emulator running on an x86 rackmount server. IBM will license their OSs for FLEX-ES, as long as the emulated CPU doesn't exceed 8 MIPS (!).
Now that Y2K is over you probably won't find many companies looking, learn something else.
/* oops I accidentally made a comment, sorry */
Mainframes are not dying. You really think that Microsoft or Linux is ever going to be able to handle the mainframe hardware? I don't think so.
Sure, Linux runs *on* a mainframe, but what you are really doing is running hundreds of seperate environments that share resources on a single mainframe. The knowledge needed to get those hundreds of instances running *well* is arcane but still useful.
If you want to learn mainframes, learn it. I think mainframes are making a comeback, and there is going to be a shortage of mainframe guys (but a glut of us Linux sysadmins).
The radical sect of Islam would either see you dead or "reverted" to Islam.
Sigs are like bumper stickers.
One day at work the hardware croaked. I was working as a sort of liazon to IT, and my department depended more on that VAX than any other department, or IT itself, so I was investigating replacements such as MicroVAXen.
What I found was an emulator called charon-vax. Test versions were available for Windows and Linux; a commercial version only for Windows. It is with some sense of accomplishment that I can report that I convinced the company to sell the Linux version commercially, on the strength of my company's order, which we delivered.
To use the emulator (evaluation or commercial) with VMS, you need a copy of the OS, which at the time was available for $20 to members of DECUS under a hobbyist license. DECUS membership was free, but they've since renamed themvelves, and I've lost touch.
--
I don't want to rule the world... I just want to be in charge of mayonnaise.
"So I'm reading all over about how companies are desperate for people who know how to work with chicks, especially now that they are so common down in the Mall. But how -- short of a course with a mate's girlfriend or some other exercise in expensive sex for hire -- can I acquire even the most basic information or experience with big tits? There doesn't seem to be many tutorials or introductions online; what would be nice, but I can't seem to find either, would be a simulator that would run on a PC. All I want to know is if I like enough to be seriously interested."
/.
You're in luck - there are several emulators available, however some of the older models are difficult to get hold of. You might want to look at this which was recently covered by
So, let me see if I have this right. I can run Hercules on my Linux box (or Win98, even) and emulate an S/390. And then I can get the IBM software that lets you run multiple, independent Linux VMs on S/390. My Linux box has now multiplied! Heck, I could even make it into a recursive Beowulf cluster.
That's step 1. Now to figure out step 2....
In my city, and I expect in others, the local two year community college teaches extension courses in what we used to call "Data Processing". Basic Tape Monkey and Console operator courses in mainframes and AS400s. JCL, CL, maybe a bit of Cobol, RPG, or some SQL queries. Nothing fancy, but the courses are hands on. These classes would not necessarily be for college credit - perhaps for adult education CEUs. Fees don't seem particularly expensive.
This is obviously dependent on your local CC's resources, interests, and local demand. But check it out.
I remember a few years back that I used a similator for a 3780 and SPF editor. It was extremely good and when I was put infront of the mainframe, I felt comfortable and I could work. I even got praised quite a bit for how quickly I picked up working on the mainframe. Little did they know that I had the simulator/emulator. Sorry that I don't remember the name of the software.
About 2 months ago I remember seeing an s/390 basic mainframe with I think 4 CPUs in one tall rack selling as is for $5000 usd on eBay. I almost started a mortgage on the thing but they hadnt booted it and gave no guanrantees, even didnt know the parts were complete. The interface was an IBM laptop that came with it. Plus it wasnt shipping to Canada and I didnt think American friends had that kind of space in their dorms.
Still keeping an eye on the eBay for such items.
"Give orange me give eat orange me eat orange give me eat orange give me you." -Nim Chimpsky
When I graduated from college in 1990 I took about the first job offered to me, one at a large midwestern bank.
I spent the first six weeks along with four other 'programmer trainees' learning the in-and-outs of the banks IBM mainframe platform as well as goodies such as COBOL, structured programming, etc.
Even today, even though I'm no longer at a bank, mainframe programming is still about 30% of my job.
http://publib-b.boulder.ibm.com/redbooks.nsf/porta ls/S390
I'll hand this much to IBM. They put out *tons* of documentation for free. It's not a ground-up overview followed by specific, real-world instruction. But, having attended more than a few AS/400 classes (no, it's not a mainframe... it's a midrange), I can tell you the instructor says "Here's your CD of Rebooks. Read them from cover to cover. This class is only to give you an overview of what you will find in them."
So, you don't go interview someplace and say "it's ok... I read the manual." But it's a starting place. And, you'd certainly sound more credible in an interview if you said "I have years of OS experince in open systems. My zSeries knowledge comes from reading Redbook X, Y and Z, and I want to learn more." Chances are, the mainframe guys have the books on their bookshelf. And, knowing the mainframe people, they refer to them.
Amateurs discuss tactics. Professionals discuss logistics.
Please don't use that big all-caps C-word. It brings back unpleasant memories.
I was reading some pornography the other day, and I got to wondering. Is there a way to get sexual experience without a partner? I thought Slashdot readers might know.
Yep. I have a set of RedHat 7.2 for the s390 CDs and I just followed the install documentation for putting it on a real mainframe. I can compile and test code on it and move the binaries to a real production machine if I so desired. It's a little slow (11 MIPS), but that probably has more to due with the hardware that I have it running on.
the good ground has been paved over by suicidal maniacs
Debian/S-390 runs perfectly well under Hercules. Have a look at:
http://www.trustsec.de/deb390/
where, among other things, you'll find an Hercules image of Debian prepared by Matt Zimmerman
I don't give a flaming rat's patootie about the DMCA, or the "don't copy that floppy" rubbish. I REALLY want to get into the mainframe admin field, and to do so, you need experience with newer mainframe OSes.
If you can give me a copy of such things, email me at J L B at T W U dot net.
I'm serious. I want to learn this stuff; DAMN copyright law. We all know it's impossible to find an entry-level position on anything nowadays, much less on mainframe operations.
Honey, I shrunk the Cygwin
There are many in the mainframe field that would "show you the ropes" pretty cheaply, but seriously it's going to take a few weeks for you to map your internal concepts from PC/Windows/Linux/Mac/Unix or wherever onto the mainframe concepts. I am technical support ( often called systems programmers) on an IBM z800 running z/OS. We once had a developer port some code from Unix or a PC (he wouldn't say which) to the mainframe. The performance sucked, because he was doing I/O one byte at a time. z/OS DASD is laid out in CKD (Count, Key, Data) format, so this basically meant the blocks of DATA on the disk were one byte long. To read 1000 bytes to 1000 I/O operations - obviously intolerable. He had never seen the logical record / physical block concept that z/OS uses, and the environment he came from, with fixed blocks (i.e. clusters) in essence handled blocking his I/O for him. This is possibly an instance where other OS's have it right, but that's irrelevant to this discussion - the problem was a conceptual one, not an OS one.
You mean like this one that's owned by some twit who only knows enough about the poor machine to describe it as "IBM S/390 Super Computer? Looks awesome!"?
Dewey, what part of this looks like authorities should be involved?
Back in my mainframe days, when PCs were first coming in, this outfit caught my attention. Seemed to offer pretty much a full blown mainframe application development environment emulation... No idea what it costs.
r es s/
http://www.microfocus.com/products/mainframeexp
go to Grizzly.com (or KBCtools.com) and order a 3-phase rotary convertor.
(i have no idea if Mach used C++.)
I'd heard that IBM had a developers agreement whereby you might license the z/OS current software for a fee. I'm not sure how much it was, but it was in the thousands of dollars. It may have even been open only to IBM employees, but I'm not sure of the details. This was *not* the same deal large installations got, because you had to submit your development plans to IBM and it probably wasn't good for high performance, either. Mostly it was for users of the P390 or R390.
That said, I think I can tell you from some experience what you will find when/if you do get some exposure to it:
* Mainframes of the S/390 flavor typically use one of these OS/s: z/OS (most likely) z/VM,
z/VSE or Linux. If they use Linux, they may also use z/VM as something akin to VMWare (I believe) to allow multiple OS images (of any type) to run simultaneously. All of the above operating systems are substantially different from each other, although z/VM and z/OS are closer to each other than they are to Linux, or any other OS for that matter.
* If you were interested in learning Linux on the S/390, you might be able to still open a free image (not just an account), on one of IBM's sites: try developerworks off the IBM.com site. This was there about a year ago, not sure if it still exists. Maybe this would be sufficient, but it would be free to you.
* Get used to mainframe file concepts, such as QSAM files, blocking, VSAM, etc. Things operate differently in this world, and certainly in a much more structured and manual way.
* Look around for a COBOL class at a local community college. If you find one, ask what machine they do their compiles on. Maybe it'll be a z/OS machine.
* Perhaps most of all, even though you may find employment doing this, always keep a resume around that doesn't mention mainframes in anyway.
Still a lot of job ads out there for archaic systems and apps. While the second hump's days are numbered, having arcane skills just might mean the difference between job and no job, in todays environment.
Even a little such knowledge helps if they're looking for someone to migrate data and/or applications off the dying mainframe. I am currently learning OS/390 and SAS in order to migrate a university department's data from that, and into M$ Access. Their databases aren't even large enough to bother with SQL Server, but back in the 80's the mainframe was the only game in town. I think I'm fortunate to get the experience (except the M$ part of it) it beats having only typical dot-com experience. All the RTFMing gets boring, but it's kind of cool that what I'm playing on, other CS students only hear of in architecture class when the prof waxes nostalgic.
But the questionis would you learn anything that you would not learn just running Linux native?
Now if you could get VM installed and run a few copies of Debian that could be very cool.
Running Debian on Hercules would be usful if you where developing for a mainframe running Linux.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
There's no need for big iron anymore; The eServer iSeries (AS/400) now runs on the PlayStation One - see http://www.theregister.co.uk/content/61/32189.html .
And yes, i am joking.
I've used the Turnkey MVS project to learn a ton about mainframes, and have a 3270 console staring at me right now. Invaluable tool for learning abou the 'guts', algthough the new and sexy stuff (ie: ISPF/SDSF) aren't there. You should check it out though...
Turnkey MVS
http://etpgw02.dfw.ibm.com/rdp.html You have to qualify but if you are serious I imagine you could get someone to sponsor you.
What does this mean? Just because of the higher cost of the equipment? I can burn CPU-time-dollars that quickly with a Linux cluster also. Though it would be easier with a couple dozen E15Ks.
Of course no one's counting CPU time for the purpose of calculating cost on Unix-like machines anymore. But that's just because there's no one to charge it to - CPU time is sold in whole system chunks. (Too bad process accounting was never updated to store more details about the process that was run, so it could actually still be useful).
You can if you can find VM but it wont be a legal copy. just run several copies of Hercules to let it do what VM would do for you.
Red Hat runs under Hercules (Alan Cox is supposed to have dunnit) as well as SuSE and Debian. Runs slow, just like on real zBoxen
Automation and Consolidation = Seperation