AIX as a flavour of Unix

[NOreen Merrick]

Hi,

just a quick query. How does AIX compare to other unix flavours? I have worked with Solaris, Hp-UX before but never AIX. Is it regarded well in the industry in terms of career experience? Is it alot different to the other flavours? I have looked at the Rosetta Stone site.

Thanks
Noreen

[A. Clay Stephenson]

When compared to most other flavors of commercial UNIX'es, AIX is a little bit dated as it derives from an earlier version of the SVID but nonetheless it is a solid OS. If you are familiar with HP-UX's LVM then you will be familiar with that of AIX because HP-UX's LVM is derived from the AIX version. I never get too hung up on which UNIX flavors an applicant has worked with because all UNIX'es are at least 98% the same --- the differences lie in the specialized administration tools and techniques. For example, SMIT is the equivalent to HP-UX's SAM. They both do very similar things. I always focus on an applicant's approach to problem solving and how good are his analytical skills. In any event, if you are a competent admin in a given flavor of UNIX, you should have no trouble adapting to another flavor in a few weeks on the job.

[Rashid Hamid]

AIX is almost the same of HPUX especially when come to LVM. For me SMIT is very powerfull System Admin tool where you can do most of the things in AIX.

[John Payne_2]

Noreen,

I consider AIX "The Bizarro UNIX". I'm not sure if you get the reference or not.

For me, it's like pulling teeth anytime I have to look at an AIX box. There just are things there that they have to do different. (No offense to the previous 2 posts...) I have spent too much time fighting SMIT to care to work on it much. (It could just be the fact that I don't work on it much, don't get me wrong here.)

Having said that, we only have 2 going on 1 AIX machines, 75 HPUX machines, 12 Solaris, and I have lost could how many Linux. I find Linux and Solaris much closer to HPUX than AIX, and prefer to stay where I am comfortable. I'd put the percentage as to the similarily between AIX and the (Solaris/HPUX/Linux) UNIXes a little lower than Clay does, maybe 90% or less, but it's that 10% that can kill you sometimes.

I recently likened working on AIX to sticking a powder blue crayon up my nose, but I'm not sure if you will get that reference either.

Maybe what I'm saying is, if you are planning to specialize over there, go right ahead. If you are planning to dabble once in a while just for fun, I would pass.

Others might have a different opionon than I do.

John

[Steven Schweda]

It's been some years since I used AIX
(version 4.1.4, perhaps?), but my impression
was mixed. For the system adminstrator, it
seemed to be very different from every other
UNIX with which I was dealing at the time
(HP-UX 10.x, SunOS 4.x, SunOS 5.x). This was
good and bad. Bad, because "different"
required extra thought for every action.
Good, because it felt as if the folks at IBM
had sat down with a UNIX spec and implemented
as much of the infrastructure as they could
as if they were making a serious,
industrial-strength operating system -- one,
for example, with zillions of uniquely
numbered errors, instead of a few dozen errno
values for every error in every program in
the world. This often made tracking down
problems about as easy as on VMS (which is a
big step up from any more normal UNIX).

Because the sysadmin commands were almost all
different from those on other systems, I had
to rely on SMIT to do things which I could do
with commands on the other systems. (I
really do miss the SMIT dude. The triumphant
biceps display after a successful command,
and the fall-on-face display after a failure
were a constant source of amusement, but I'm
easily entertained.)

In general, it worked well. Porting software
to AIX usually required some extra work
because of AIX peculiarities, but nothing
horrible in the stuff I was doing.

[Sorrel G. Jakins]

I can get things dome in AIX (pronounced 'aches') but it is usally a bigger deal than it need to be. IBM support is good, so if you have thaqt then the support people are very nice and helpful and you can get the job done.

HPUX support is IMHO better, and of course with HPUX and Lin*x you have this excellent resource (http://itrc.hp.com) which cements my preference clearly on the side of HP. Whatever you decide or have foisted upon you by management, good luck.

Sorrel Jakins

[dirk dierickx]

as usual, the basic unix commands are the same as everywhere, perhaps with a few differences in parameters now and then.

it is, again, if you try to do more specific stuff (which most admins will be doing), that you run the flavour specifics.

anyways, i love the unix principale - KISS (keep it simple stupid). and for me solaris and linux fit that matra the most, while hpux and aix are making things more complicated as it should be most of the time.

[Mobeen_1]

Noreen, AIX is pretty good and as many have indicated on their responses LVM is the same as what in HPUX.

Having worked for some time on AIX, i could definetly say that it is
1. Solid OS

2. The diagnostic tools that come with it are pretty good

3. Its system management tool (smitty) is easy to use

4. Some diagnostic utilities like "diag" are very good

I would definelty rate it as amongst the best if not the best.

In terms of career experience...Industry terms...if your question is directed at the compensation aspects...then that really depends on the supply demand situation in the geographical location that you stay :)

regards
Mobeen

[Robert-Jan Goossens]

Hi Noreen,

If you are allowed to follow a training for AIX, try to attend to this course. It is a 4 days training for experienced Unix admins.

AIX Jumpstart for UNIX Professionals (AW18V0BE)

Good luck.
Robert-Jan

[Ralph Grothe]

Hi Noreen,

my feeling towards AIX are very much the same as John expressed them so vividly.
I always feel a bit coerced into using their SMIT admin tools for so common tasks like volume and filesystem extension or user management that I would execute on all other flavours of Unix that we host simply within a few command line invocations at the shell, or by editing a config file here and there.
I admit that such an attitude of system administration nowadays in an ever complexity rising envirenment may be quite anachronistic.
Also do I little or not at all care about an operating system's or application's potential for careeristic exploitability.
Yet another luxurious attitude one cannot afford these days, and which explains my career deadlock I suppose.

[sathish kannan]

hi Merrick,,

as a i have used both HP and AIX (note that I put HP at first :) ), I found AIX as most simple and effective because of SMITTY. The drivers, software installation, sys admin tasks are more similar to HP-UX.

In terms of LVM, HP always prefers to use command line whereas IBM prefers SMITTY. AIX comes with lots of inbuilt tools like perfmon etc.

for me one draw back with AIX is their ODM which is like registry in Windows but defitely 100 times better than MS.

all the best

regards
sathish

[Mike Shilladay]

Hi Noreen,

I personally cannot stand AIX. It is robust enough but I just do not like it. For example I like the command line to create a new logical volumes and in HP-UX it is easy, on AIX you almost have to use 'smit', although I have worked out how you do it on the command line but there are so many switches. Printers are a real problem for me on AIX, as the commands are not the same. So in summary my opinion is that I would rather work on any other UNIX except AIX.

Mike

[Florian Heigl (new acc) · Accepted solution]

I'll spent my two cent here, as I still admin a few aix 5.3 boxes.

AIX is very much different
AIX is REALLY weird.
AIX does UGLY things to your brain.
AIX has two modes, one extremely safe mode (using smit or highlevel commands) that wraps up every single command to ensure no one is able to mess up, and one that is 'quite' normal, but You HAVE to know what you're doing, to much more extent than on other unix systems (I highly recommending AIX LVM & Troubleshooting II prior to touching an AIX box).
AIX is the most robust UNIX I know. Last year we decomissioned a few systems of various ages. After working with the author of scrub (extremely reliable diskworking software) to fix a few glitches in the AIX port I wiped about 10 systems' root disks. I got into big trouble as I expected the boxes to die sometime after the disks, and found they were still up and running two weeks later on. They sure noticed invalid disks headers, etc. but were up and accessible, which means I could actually have recovered them in that state w/o a reboot.
AIX has a very good pricing, You get partitioning, fine grain resource control, a resource manager and disk mirroring all in the base OS.
AIX has robust clustering, too
AIX 5.2 and above have mature multipathing support, I personally consider far more reliable than i.e. EMC^2 PowerPath.
AIX is a PITA for 3rd party software, the linker is a mess, the compiler is a mess, and their OSS bundles are an insult (i.e. they deliver lots of software as linux-ppc rpms that will run in binary emu - what point is there left buying a fast power5 cpu if you waste all that on emulating a 32bit ppc *linux* host?)
AIX is a PITA for things like DCE, OVO and more, too
AIX is incredibly ugly
AIX has an structured (almost POSIX draft compliant) error log that is even MORE ugly
AIX is a SysV kernel with BSD runlevel(not) environment, thus no singleuser mode!
AIX won't be able to boot if / is full as it needs to regen /dev on boot
AIX boxes have *unbearable* boot times
AIX (and rs6k systems) have a number for every error and 3 800-page manuals listing error codes for things like 'invalid boot device'.
Thus you can let IBM CEs have an heart attack by controlling the systems lcd panel to display '888'

Last, and this is the only thing in the whole You can't come by by knowledge/experience, and the thing really forbidding to run AIX for anything production grade:

You have to deal with IBM's totally ignorant, incompentent support lines. There is no way you can trust any data to that.

florian

(as the only person trying to make bacula and netbsd pkgsrc work on AIX I'll even state it wasn't two cent but an euro)

[Florian Heigl (new acc)]

Let me add that using smit[*] either means you came back from a six-week vacation or you simply never found out about the right commands, but this is some of the magic of aix - while on hp-ux using sam can be risky (i.e. network config on multihomed systems), smit keeps you from messing up.
using the command line lowlevel commands (not installp, mklv, but the ones called by these) is possible and offers extremely valuable flexibility, it's even safe for the structuredness of those, but it requires you to think like someone working for ibm.
that is not good. five out of five ibm customer engineers i had onsite ran their nose into the turning glass access lock that leads into the datacenter. No kidding, and You don't want to like that.

[*]there's even websmit, which offers a sexy java gui.

[NOreen Merrick]

Hi Florian,

just wondering. What are the most common problems on AIX. Am heading into role with majority AIX boxes and wondering what things I should swot up on. I havent AIX experience but still have been hired!!


Thanks
n

[Florian Heigl (new acc)]

Like A. Clay said, often it's more important to have a good candidate than an experienced one.

hmmm. most common issues... we have had very little issues, mostly mainteanandce taks;
replacements of disks, cache batteries and power supplies.
we had to open calls for little stuff, i.e. coredumping daemons and such, and our biggest issue EVER was ibm's custom firmware for a gigabit ethernet adapter. we had to turn off tcp offloading, because it was a slight bit too standards-compliant, sudden loss of connectivity if a host the same network connected; the net was a class C with /23 masking.

IBM really loves to mess with every possible bit of firmware that can be messed with, and if I could give only one advice it would be: always know which firmware is on your box, on your service processor, on your disks, adapters and everything within visible range, and also know which is the most current f/w, and which is needed.

now head over to news://comp.unix.aix and ask for other people's most common issues :>

[gfalk]

Bit late of a reply, but if you can find smit/smitty, you can get essentially anything that you'd do out of the command-line (including the actual command) from it.

I've worked with AIX off and on over the past decade, and as others have mentioned, it's a little off some of the more common Unix flavors, and a little more cumbersome in some areas to deal with; however, the TCL scripts written by IBM for system administration are not at fault for this. I rarely go into smitty for some of the things listed in this thread, and here's why:

If you can get into a tty session, launch smitty, you can find out very quickly instead of going through smitty to create the logical volume (as someone mentioned earlier), use the esc-6 (or F6) sequence after you have your parameters filled in, and it'll give you the exact command-line it will use to create the lv (mklv is the script name).

Once you have that you can script out logical volume creation, or find any other command-line equivalent to smitty for volume group creation (mkvg), off-lining volume groups (varyoffvg), etc, just by poking a bit around in smitty. It is extremely robust, and much as I once previously hated to admit it, the IBM implementation is rather elegant.

Additionally, the IBM online documentation now is extremely good, especially now that the Redbooks are now publically available free-of-charge in PDF format.

The p5 system's have some questions to be answered to see if its a good fit in an environment (hardware boot times are slow, but setup a LPAR and OS reloads take around 5 minutes rather than 30 or worse), but any competent sys admin solid with another flavor of Unix can navigate AIX successfully.

[Stephen McGill]

I have worked with AIX for years and love it. I was trained on Solaris as well, and find it to be much more awkward to use.

People have mentioned the boot time: Once the hardware has booted one time, you don't have to do it again(unless you had a firmware update, or part replacement perhaps), you just shutdown and reboot the OS, which is almost instantaneous. There is no 'hardware boot' to wait through.

You can have multiple instances of AIX running on 1 physical system. You could have prod and dev in seperate partitions on the same piece of hardware, allowing for exact hardware concurrency.

Smit is cool, if you want to use it, but there is no need to use it. After you have used the commands, they become second nature, just as they have on whatever flavor of UNIX you currently use.

AIX 5.3 has a virtual lan built in for use on p5 and above equipmnet. You can pass packets on the backplane at a much higher rate than through PCI... adapters. ex. Between web and app server, or app and db.

AIX has a nice tool for keeping track of all the microcode on the system, called Inventory Scout. You run the tool, it compares what's on your system to the latest out, and gives you a report of the deltas.

My .02

[Stephen McGill]

I have worked with AIX for years and love it. I was trained on Solaris as well, and find it to be much more awkward to use.

People have mentioned the boot time: Once the hardware has booted one time, you don't have to do it again(unless you had a firmware update, or part replacement perhaps), you just shutdown and reboot the OS, which is almost instantaneous. There is no 'hardware boot' to wait through.

You can have multiple instances of AIX running on 1 physical system. You could have prod and dev in seperate partitions on the same piece of hardware, allowing for exact hardware concurrency.

Smit is cool, if you want to use it, but there is no need to use it. After you have used the commands, they become second nature, just as they have on whatever flavor of UNIX you currently use.

AIX 5.3 has a virtual lan built in for use on p5 and above equipmentt. You can pass packets on the backplane at a much higher rate than through PCI... adapters. ex. Between web and app server, or app and db.

AIX has a nice tool for keeping track of all the microcode on the system, called Inventory Scout. You run the tool, it compares what's on your system to the latest out, and gives you a report of the deltas.

My .02

[Reshma Malusare]

Hi,
As you know basic platform for all unix flavours is same..they just differ in their tools used... AIX is updated flavour..which has demand in market....SMIT is helpful tool in AIX which mostly like our SAM...Also, LVM concept is same for both AIX & HP-UX....if you know HP-UX well then it will not be difficult to understand AIX.

Thanks & Regards
Reshma