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."

Comments

Here is a slightly dated...

[Sevn]

yet excellent page on just this topic. :)

HERE

Hope this helps!

The Hercules System/370, ESA/390, and z/ Emulator

[Jeremiah Cornelius]

Hercules is an open source software implementation of the mainframe System/370 and ESA/390 architectures, in addition to the new 64-bit z/Architecture. Hercules runs under Linux, Windows 98, Windows NT, and Windows 2000.

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.

Mainframes are something you *learn* to like...:')

[mellon]

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? :'}

Buy a used mainframe

[HotNeedleOfInquiry]

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.

Re:Buy a used mainframe

[Yonder Way]

Actually I think that a mainframe may fit better, considering (from IBM paradigm) that the mainframes are more vertically oriented and the AS/400's more horizontal.

Think of a mainframe as a refrigerator form factor (at least the late model ones) and the AS/400 as a very tall coffee table.

The black thing in the foreground of this picture is a late model IBM mainframe. It basically takes up as much room as any 19" equipment rack (or, like I said, a refrigerator).

The downside to an AS/400 or a mainframe no matter which way you go is the exotic (for residential) power hookup requirements. Many local governments preclude residential zoned lots from having three phase power, which could really screw you if you want to bring home the big iron.

Re:Buy a used mainframe

[crmartin]

An AS/400 would be kinda fun, but it is in no way a mainframe. In fact, as AS/400 is an emulator for a lovely machine of immensely weird architecture called the System/38 -- it had a "tagged" architecture, which means that it's essentially object-oriented hardware. It also has a 120-bit address space, in which all devices (memory, disk, tapes, floppies, networks etc) simply occupy parts of the address space. The emulator makes this rather baroque instruction set run on RISC-y underlying processors, and makes the processors transparent to the rest of the system: user software doesn't even know it's on PowerPC or something weird else. (There was even some discussion of doing VLIW processors, although I don't know what ever came of it.)

The other amazing thing is that OS/400 as of V3R6 has the whole bottom layer implemented in C++ from bare silicon on up. So far as I know, it's the only commerical OS that was actually implemented from using C++ and object-oriented all the way. (I participated in teaching the folks at IBM the C++ they needed to do this.)

The point is, though, that the IBM/360 series of mainframes are not the same.

Re:Buy a used mainframe

[Seraphim_72]

Three Phase ?? Really?
I know what it is used for with moters but why on earth would you need it for a computer? The only thing I can think of is that you would want it to level out the power, but surly there are better ways.

Seraphim

Re:Buy a used mainframe

[Tower]

Very true - the AS/400 is not a mainframe (though some marketing folks are trying out the name "midframe" here and there).

>There was even some discussion of doing VLIW processors, although I don't know what ever came of it.

The eServer iSeries (AS/400) now runs with the POWER4 processors - see http://www.ibm.com/iseries for products/details.

(and yes, I work for IBM... on iSeries I/O products)

Re:Buy a used mainframe

[TheSunborn]

No version of qnx is using Mach. qssl made their own kernal. For qnx6 that kernal is called Neutrino 2.

And even photon(The gfx system) is using c bindings, so I really don't think they have used much c++.

Martin

Re:Buy a used mainframe

[drinkypoo]

Modern AS/400 systems are full tower case designs. Many of them have integrated UPSes in the base, which must make them heavy as hell but extremely unlikely to fall over.

It's really very easy

[elmegil]

The same way as everyone else got mainframe experience in the old days: Entry Level Position.

Re:Simulator?

[Lionel Hutts]

That's either the least educated comment I've read around here in a while, or the best-crafted troll. In any case, I'll bite:

Do you have any idea how little raw CPU power (not that they call them CPUs) a traditional mainframe has? They said mainframe, not supercomputer!

Yes, yes, they have lots of fancy I/O processors and whatnot, and some modern big iron is different, but there should be no problem running simple software on an IBM mainframe simulator, if one exists and you don't actually intend to support many users on it.

IBM Redbooks

[Grotus]

IBM has pretty decent documentation on their stuff, at least the AS/400 docs were good.

Go here for the zSeries and S390 docs.

Re:The Hercules System/370, ESA/390, and z/ Emulat

[peterjt]

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.

teh gibson.

[Anonymous Coward]

j00 mu57 h4x0r 73h g1b50n, 4n|) |)0wn104d "garbage"

Training

[Mr. Piddle]

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.

Re:Training

[Bitsy Boffin]

You are right.

Companies are no longer interested in training people to do a job, you only have to look at job postings in your local newspaper to see that - 'must have x years experience in some obscure system' (one I saw recently was funny, "must have 5 years commercial experience with ASP.Net").

I wanted to move from writing web applications to more traditional C/C++/Java stuff a year ago - I'm a BSc. in Computer Science, had been working several years in the web. While my CV was good enough to get me on the short list for more or less all I applied for, I would always be dropped because I was not "current" in C, C++ or Java - seems because I didn't have the "right" experience (not in those languages) I was no good to them.

Non tech people (the ones who do the hiring) don't understand that being a Comp Sci. grad means that I CAN do it, it's all the same, just syntax, and that my commercial experience IS relevant. And so they take someone straight from Uni who while being "current" in the language-de-jour has no experience, over the developer with valuable experience who happens to be not current in the language-de-jour but could be within a week or two.

*sigh*

Re:Training

[Lumpish Scholar]

... [is] there such a surplus of qualified candidates milling about that ...

It doesn't matter how you finish the question, the answer will be "yes".

Ug indeed.

It just seems that ground-floor opportunities are a myth.

The only ground-floor opportunities today are the ones you get a few seconds after they throw you out.

Re:Training

[ComputerSlicer23]

Hmmm, don't take this the wrong way... but C++ isn't something you pick up in a week or two, I've been coding in C/C++/ObjectiveC professionally for 6 or 7 years now. Sure you can use it to do everything you could so in say Pascal in a week no problem.

A couple of weeks of C++ experience won't teach you the nuances of the STL, how templates work, the strange rules about operator overloading. It won't teach you in's and out's of the pretty large C/C++ standard libraries. You won't know anything about the sublties of the multi-inheritance issues. You won't know about the nooks and cranies involved in overloaded function call parameter resolutions. That's the kind of expertise you need to be able to do serious C++ work. It's something that takes at least a year or two of experience, and dedication to learning the ins and outs of it all. They are better off paying some fresh out of college grad less money to learn in all likelyhood then they are you. They have the same degree you have, that you claim will make you competent in a couple of weeks. Why should they pay you extra?

You've got it all backwards, the semantics of the language are what are important. In fact, I'll go so far as to claim that your experience might make you a worse candidate for using C++ then your fresh out of college grad. You have knowledge and expectations about how you think things should work. You think you know what the semantics are. However, subtle differences in the semantics can lead to very poor code, where you end up fighting the language the tools to get the job done.

Java, which I don't know, I am told is really difficult to be very good at, if you aren't extensively familiar with the ins and outs of the areas. Simple stuff with J2EE, like certain containers can't deal with threads. Stuff like how overloading works, the difference between the object type Integer, and the base type int. The differences between the various JVM's. The sublties of hooking up the various intrumentation tools. There is an extremely large standard library, and knowing how it works, and which pieces are how old, and what is compatibile with with versions of the JRE's is very important. Just knowing the syntax, and that inner classes are a feature, and that there are no pointers, and there are no functions not attached to a class, doesn't make you Java programmer. Sure you can have a cursory knowledge of Java in a couple of weeks. Great, I'm not terrible interested in paying you experince programmer wages so you can learn the tool. There are entry level jobs out there for Java. They'll be thrilled to have someone with programming experince.

Just because you have a degree in Astro-areo dynamics, and have experience designing parts on for the Shuttle engine, doesn't mean you have the necessary skill to be a drop in replacement for a engine designer for Dodge trucks. A guy fresh from college who studied the Engineering methodologies of Dodge for the 6 months in a case study, is probably much more qualified then you are, for very similar reasons.

My first programming gig, was pretty much, we higher you for twice what McDondald's pays you, and we'll throw you in the deep end of the pool 3 months, if you still floating at the end of that, your a keeper. I got plenty of lessons at the school of hard knocks, they had a couple of very good senior programmers who kept the rookies on track, and bailed them out if things got out of control. I made good money for what I knew, and 2 years later, I did in fact know a lot about C/C++. My next job, I spent a bunch of time writting ObjC. Spent 18 months learning the ins and outs of the OpenStep Runtime making not much more the the first job, and I learned a lot about Oracle and being a DBA. I learned a lot about Solaris, Linux, and WindowsNT during all that too. Then, I finally got a good job, for someone who had experience in C++, and needed some expertise in doing SA work, and I had to build a schema, and pick a backend RDBMS system to run the company's core data on. I finally was considered worthy of the task.

Kirby

Re:Training

[Carpathius]

At least in part I disagree. I've been doing professional programming and application development for over fifteen years now.

There is a *big* jump from procedural programming to OO programming, and there are those who I've seen have major problems making that jump. But that's not true in all cases. Once you understand the basic techniques in procedural and OO development, it's not that big a jump to move from language to language. It's mostly a matter of learning the libraries.

Can a C programmer learn C++ in two weeks? Maybe. It depends on many things, not the least of which is how good a developer the person is already. Will the best developer know all the ins and outs of C++ after two weeks? No, but that's unimportant. The best developer will *know* s/he doesn't know everything, and will be able to pick up those things as s/he progresses. Will he or she be competent? Yes. Will he or she be productive? Yes.

It really depends upon the person. Once when I left a position, the guy who was filling my spot didn't know why he should care about the difference between disk and RAM. He'll never be a decent developer. Yet there are people out there who can pick up Java when all they know is COBOL. (Real example.)

My point is that once you are truly a *good* developer, then most of the rest of it *is* syntax and libraries. OO is just another type of syntax, and someone who really understands programming will pick it up as well.

Sean.

Entry Level Postion ? (Re:It's really very easy)

[OzPixel]

I thought they were all in India these days.

Re:The Hercules System/370, ESA/390, and z/ Emulat

[Ratbert42]

A number of our developers hypothetically could possibly be running Hercules and some of the latest and most sophisticated IBM software and it (hypothetically again) kicks ass.

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.

Not as desperite as you think

[bluGill]

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.

Don't Bother

[perljon]

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.

Re:Don't Bother

[Hellraisr]

Mainframes are dying are they?

Also, COBOL has been around for 50 odd years or so.. it has outlived other languages, and companies love it because their stuff that's years and years old will still compile and run, so they don't have to pay someone to rebuild from scratch.

My guess is you're an x86 programmer, aren't you? And you think that just because you never logged into a mainframe that nobody else is.

The biggest companies in the world still use them heavily, and as long as those companies still want the machines (they still do as their programs already run on them, and do so quite well), IBM et al will NEVER discontinue them.

Join the Navy

[jadis_194a]

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.

Tutorials and mainframe emulators

[Animats]

There's an online VM tutorial from IBM.

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 (!).

Re:How To Simulate A Mainframe In Five Easy Steps.

[Poeir]

An iron bar with a rubber handle for gripping might come in handy.

Ah, so that's what a cluestick's made of.

VAX emulation

[polymath69]

The VAX may technically be a minicomputer, but when I entered the machine room for the first time, it was awfully big and impressive. I went on to work with them in college, and after.

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.

Re:Obtaining Girlfriend Experience w/o a Girlfrien

[skinfitz]

"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 /.

Re:Training on AS/400?

[RobertEdwards]

Two or three years ago there was a consulting firm that rented time on their AS400 for not very much a month advertising on the AS400 newe group. Hop over to groups.yahoo.com or your favorite newsreader and do some looking there. Ask -- it's quite friendly as usenet goes.

IBM publishes all their reference manuals for both the iSeries and zSeries OSs on line for free access. Go to www.ibm.com and search around for eSeries, OS400, OS390 and Reference. Also search around for :Redbooks and Redpapers -- that's what they call techical whitepaper, and they're a good resource.

ESA/390 Emulator

[LauraW]

Hercules is an open source software implementation of the mainframe System/370 and ESA/390 architectures

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....

Re:ESA/390 Emulator

[Jeremiah Cornelius]

This was even done by someone on the mailing lists.

I think the person with enough time on his (her) hands coud run Hercules on OpenMosix.

Ouch....

Check Community Colleges

[RobertEdwards]

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.

How about IBM's redbooks?

[Bravo_Two_Zero]

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.

Re:'Borrow' some time

[zootread]

Just hack into one, and 'borrow' some time on it.

This was modded down, but is actually good advice. This is how I got much of my UNIX experience when I was young and didn't have money. Just don't do anything malicious. And don't get caught.

Someone contact me with mainframe OSes, please.

[JessLeah]

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.

Re:Linux on IBM negates "mainframe skills"?

[THEbwana]

They dont migrate away from zos to linux. They migrate from win and various unices to linuximages running in lpars on zos machines.

- This means that they need zos operators to setup the zos environment and linuxadmins to run the linux images running on the zos machine.
The problem lies in the availability of zos veterans who didnt stop learning things 10-20 years ago (and who are not retiring within the next couple of months). These veterans are needed to setup the system lpars, wlm, etc etc to provide the logical areas where linux is supposed to run. If this is not done properly, there will be no benefit in running Linux on zos compared to running Linux on i86 clusters -> IBM will sell less zos hardware.

The biggest problem for IBM (IMHO) is that it's so hard to get mainframe experience -> no one learns the platform -> they sell less hardware.
I recently saw a WebSphere zos assignment in London paying 2500 GBP / day. That's roughly 90 000 usd / month, clearly reflecting the supply and demand situation in this market segment. If IBM wants to continue selling their zos hardware they will have to give the slashdot crowd an easy and cheap route to gaining mainframe skills. /m