4 ms·

AIX was/is one of the few big commercial unixes I've never got to touch, is it worth it?

ourmandave 4y ago
No. AIX is the "you can't have nice things" version of linux. Command options you take for granted aren't there in AIX. Search on Unix stack exchange and there's always a more complicated "here's how you do it in AIX."
- SpaceInvader 4y ago
  I disagree. I used to be an AIX administrator for well over a decade, got certified in basically everything related to AIX being on the side hard core FreeBSD user (still have some servers). In my opinion AIX is indeed different, but rock solid and fun to work with.
  - ourmandave 4y ago
    I've been since AIX v3. Moving to linux 10 years ago was like coming out of the stone ages. But it's the same for every language. Something that's a stupid hard problem that takes a huge effort to solve is suddenly a one-liner in the next release.
- Nursie 4y ago
  Does the unix rosetta stone page still exist? That was a godsend when trying to move between half a dozen commercial unix systems 15 years ago.
- icedchai 4y ago
  AIX pioneered technologies, like logical volume management, journaled file systems, etc. way before they were available in other Unixes. LVM existed for Solaris, but was an expensive third party add-on (Veritas Volume Manager, etc.) It definitely had a weird feel to it though!
inkyoto 4y ago
It is hard to say about now, for most of the interesting AIX features are tightly coupled to the IBM hardware (e.g. dynamic CPU re-/allocation across LPAR's and a gazillion of other things), and the hardware is rare to come by nowadays. For its time, though, AIX was highly innovative and was perhaps the first UNIX that bundled a LVM and a journaling file system into the standard system distribution (and not as separately purchased commercial products). It also has a single set of .a libraries which are both used as dynamic AND static libraries (courtesy of the XCOFF object file format). It also has uniform and very tidy naming conventions for command line utilities, e.g. anything that can create something (e.g. a user account, a user group, a logical volume etc) is prefixed with mk-, mutating commands are prefixed with ch-, destructive operations have the rm- prefix. Pervasive performance metrics and counters across the entire system are also cool. Lots of other small niceties I have forgotten about.
- inkyoto 4y ago
  Oh, yeah, AIX is perhaps the only UNIX kernel out there that can preempt itself out of RAM into a swap space in nearly its entirety under a heavy memory shortage pressure, with the exception of the disk interrupt handler – to swap itself back in later, thanks to its peculiar VM subsystem design. It is no longer a material feature to have but is cool nevertheless.
- pjmlp 4y ago
  My last stint with Aix was in 2002, however I still have found memories of using a UNIX that in some corners felt a bit like Windows thanks XCOFF.
- random314 4y ago
  JFS! You had the option to upgrade to Veritas' VxFS and VxVM.
Nursie 4y ago
I mean ... I used to write software in C that targeted AIX as well as HPUX, Solaris etc back in the 00s. It was fine. Posix compliant, had a C compiler, debugging was OK with dbx (IIRC you could get ddd to use dbx as its subordinate debugger, which was helpful). The main selling point AFAICT was that it was on POWER, which has always been a pretty competitive set of processors, often faster than x86/64 in some (no doubt carefully massaged) metrics. I think, like a lot of IBM systems and a lot of commercial unix, at that point it was ahead of the game in its system-paritioning capabilities, having LPARs much like z/OS (and Solaris Zones I guess). I don't know if it has any other major unique selling points, as a C programmer I tended to focus on commonalities rather than differences!
- chasil 4y ago
  Zones all run under the same kernel. I'm guessing these lpars all have separate kernels.
  - tbrownaw 4y ago
    My understanding is lpar - VM or domU or such wpar - zone or jail or container or such
  - classichasclass 4y ago
    Correct, LPARs are akin to hardware partitions. Even my single-instance personal box has an LPAR and doesn't run on the metal (it just gets everything that's installed).
  - Nursie 4y ago
    Fair enough, I did say I was an application programmer!
- tssva 4y ago
  LPARS would be more like Solaris dynamic domains not zones.
Spooky23 4y ago
I really enjoyed it, although Solaris was easier as the user base was bigger. My usage was circa 2000-2005. I loved smit and smitty, and would start new interns and juniors on AIX because the command lines to perform tasks would be generated and allow them to become productive quickly.
- chasil 4y ago
  An AIX admin told me in the late 90s that there were no kernel tunables (i.e. sysctl.conf). That would be very nice. The jfs journaling filesystem was much better than ufs until sun got zfs into the formal distribution
  - classichasclass 4y ago
    There's no sysctl, but there are definitely tunables and there's a whole subculture of jackbooted thug AIX admins who spend all day messing with them for peak performance. I'm not one of them, but I remember tweaking the network stack a bit on my 4.1 system back in the day.
jmclnx 4y ago
Depends on what you mean by "worth it" :) I develop applications (c) on AIX and it is a bit different, I find it rather close to the BSDs. There are minor oddities, but I think it is rather good, and I personally like it. As time goes forward, I think RHEL is going to be the direction. It is a bit sad to see these proprietary UNIXs fall by the wayside, but most of the reason is their fault for the restrictive licenses they have.
sillystuff 4y ago
I'm surprised at all the positive things being said about AIX in this thread. I thought it was pretty terrible (my priors were SunOS, Solaris, HP/UX, IRIX, Linux, BSD). Personally, I preferred any of the above over AIX. AIX configuration was opaque with a windows registry style setup. All the standard utilities like sed, awk, etc., were versions from 1970. It was incredibly frustrating to use. They did supply some gnu software (IBM called it "linux" software), but it was managed through a second, separate, package manager, bare rpm. Decade(s) after every other nix had snapshots, the way to get a consistent backup on AIX was to break your boot disk mirror and backup the orphaned disk (while praying you didn't have a disk failure). Everything was spawned directly out of inittab. No sys-v/rc/etc. scripts. A hard down could break the journal on their filesystem rather than having the filesystem journal save your data. An fsck would not fix the journal. Most free software did not "just build and run" on AIX. Just about anything using autoconf required a custom wrapper around AIX's malloc to prevent it from segfaulting when being run, or fixing autoconf scripts to not mis-detect missing capabilities in AIX. AIX was not a first tier system for many vendors. I had to spend time in a debugger providing info to our SAN vendor on issues with their agent for AIX (we never had issues with their software for Solaris, Linux, or Windows). The hardware was funky. They did "neat" things like sharing a single CDROM drive between an entire rack of servers. But, to re-assign the CD drive, the IDE bus had to be re-assigned, as well as the PCI bus. And, invariably something would be blocking this, so "neat" in practice became a PITA. On the positives, AIX was stable once everything was dialed in, just like any other NIX. It was also trivial to create a bootable DR restore ISO for a system. And, their debugger was pleasant to use when diagnosing core dumps. "It used to be said that AIX looks like one space alien discovered Unix, and described it to another different space alien who then implemented AIX. But their universal translators were broken and they'd had to gesture a lot." -- Paul Tomblin
- dosman33 4y ago
  Sounds like perhaps like most of your experiences were with pre-AIX version 4? No system is perfect for sure. By the time I started using AIX it was with version 4 and was moving to 5 and I can't say any of the problems you've described were things I had encountered with it. Certainly I had lots of problems though. Not suggesting you didn't experience these things though of course.
neilv 4y ago
When the RS/6000 launched, AIX had some neat system management OS features and hypertext documentation that was better than any of the other workstation vendors at the time. Also, the RS/6000 and/or AIX was noticeably fast at some things. I remember a Systems Engineer being amazed that you could invoke a shell window (aixterm, IIRC), and it snapped instantly onto the screen, no lag.) The workstation vendors were often leapfrogging each other, but on that one metric, 0 perceptible time was new. I don't remember how compiles compared. If you can pick up an RS/6000 on eBay, with licenses and install media, it might be a little fun to play with. And maybe either check that GCC will work, or that you're getting license and media for the compiler. Today, though, there's so much neat stuff to play with atop Linux alone, that you could never get through it all. And, if you haven't already made your fortune and retired from paid work, things atop Linux are also more likely to be more directly relevant to paid jobs for current production environments, or at least to be better for resume keyword-matching.
yourapostasy 4y ago
If you have a pressing business need for near-mainframe security and/or resilience for monoserver applications, and are willing to spend the money for it, its hardware, staffing, and the platinum IBM Support and training, in some cases it is still cheaper than rolling your own under Linux. IBM packages a one-stop shop for a RAS experience [1] that would need a deep bench of engineering talent to reproduce were you to roll your own equivalent in Linux. So some customers would rather pay IBM than try to build such an organization and for them, AIX is worth it. Generally however with IBM’s rampant offshoring of support leading to a tremendous loss of institutional knowledge and rapid turnover of the offshore support teams, I’ve found unless you’re signing 7-9 figure renewal checks and paying for enhanced support, the support experience is way worse than it was around the 1990’s but still marginally better than other vendors. [1] https://www.ibm.com/downloads/cas/2RJYYJML https://www.ibm.com/downloads/cas/2RJYYJML

No. AIX is the "you can't have nice things" version of linux. Command options you take for granted aren't there in AIX. Search on Unix stack exchange and there's always a more complicated "here's how you do it in AIX."

SpaceInvader 4y ago
I disagree. I used to be an AIX administrator for well over a decade, got certified in basically everything related to AIX being on the side hard core FreeBSD user (still have some servers). In my opinion AIX is indeed different, but rock solid and fun to work with.
- ourmandave 4y ago
  I've been since AIX v3. Moving to linux 10 years ago was like coming out of the stone ages. But it's the same for every language. Something that's a stupid hard problem that takes a huge effort to solve is suddenly a one-liner in the next release.
Nursie 4y ago
Does the unix rosetta stone page still exist? That was a godsend when trying to move between half a dozen commercial unix systems 15 years ago.
icedchai 4y ago
AIX pioneered technologies, like logical volume management, journaled file systems, etc. way before they were available in other Unixes. LVM existed for Solaris, but was an expensive third party add-on (Veritas Volume Manager, etc.) It definitely had a weird feel to it though!

inkyoto 4y ago

It is hard to say about now, for most of the interesting AIX features are tightly coupled to the IBM hardware (e.g. dynamic CPU re-/allocation across LPAR's and a gazillion of other things), and the hardware is rare to come by nowadays. For its time, though, AIX was highly innovative and was perhaps the first UNIX that bundled a LVM and a journaling file system into the standard system distribution (and not as separately purchased commercial products). It also has a single set of .a libraries which are both used as dynamic AND static libraries (courtesy of the XCOFF object file format). It also has uniform and very tidy naming conventions for command line utilities, e.g. anything that can create something (e.g. a user account, a user group, a logical volume etc) is prefixed with mk-, mutating commands are prefixed with ch-, destructive operations have the rm- prefix. Pervasive performance metrics and counters across the entire system are also cool. Lots of other small niceties I have forgotten about.

inkyoto 4y ago
Oh, yeah, AIX is perhaps the only UNIX kernel out there that can preempt itself out of RAM into a swap space in nearly its entirety under a heavy memory shortage pressure, with the exception of the disk interrupt handler – to swap itself back in later, thanks to its peculiar VM subsystem design. It is no longer a material feature to have but is cool nevertheless.
pjmlp 4y ago
My last stint with Aix was in 2002, however I still have found memories of using a UNIX that in some corners felt a bit like Windows thanks XCOFF.
random314 4y ago
JFS! You had the option to upgrade to Veritas' VxFS and VxVM.

Nursie 4y ago

I mean ... I used to write software in C that targeted AIX as well as HPUX, Solaris etc back in the 00s. It was fine. Posix compliant, had a C compiler, debugging was OK with dbx (IIRC you could get ddd to use dbx as its subordinate debugger, which was helpful). The main selling point AFAICT was that it was on POWER, which has always been a pretty competitive set of processors, often faster than x86/64 in some (no doubt carefully massaged) metrics. I think, like a lot of IBM systems and a lot of commercial unix, at that point it was ahead of the game in its system-paritioning capabilities, having LPARs much like z/OS (and Solaris Zones I guess). I don't know if it has any other major unique selling points, as a C programmer I tended to focus on commonalities rather than differences!

chasil 4y ago
Zones all run under the same kernel. I'm guessing these lpars all have separate kernels.
- tbrownaw 4y ago
  My understanding is lpar - VM or domU or such wpar - zone or jail or container or such
- classichasclass 4y ago
  Correct, LPARs are akin to hardware partitions. Even my single-instance personal box has an LPAR and doesn't run on the metal (it just gets everything that's installed).
- Nursie 4y ago
  Fair enough, I did say I was an application programmer!
tssva 4y ago
LPARS would be more like Solaris dynamic domains not zones.

Spooky23 4y ago

I really enjoyed it, although Solaris was easier as the user base was bigger. My usage was circa 2000-2005. I loved smit and smitty, and would start new interns and juniors on AIX because the command lines to perform tasks would be generated and allow them to become productive quickly.

chasil 4y ago
An AIX admin told me in the late 90s that there were no kernel tunables (i.e. sysctl.conf). That would be very nice. The jfs journaling filesystem was much better than ufs until sun got zfs into the formal distribution
- classichasclass 4y ago
  There's no sysctl, but there are definitely tunables and there's a whole subculture of jackbooted thug AIX admins who spend all day messing with them for peak performance. I'm not one of them, but I remember tweaking the network stack a bit on my 4.1 system back in the day.

jmclnx 4y ago

Depends on what you mean by "worth it" :) I develop applications (c) on AIX and it is a bit different, I find it rather close to the BSDs. There are minor oddities, but I think it is rather good, and I personally like it. As time goes forward, I think RHEL is going to be the direction. It is a bit sad to see these proprietary UNIXs fall by the wayside, but most of the reason is their fault for the restrictive licenses they have.

sillystuff 4y ago

I'm surprised at all the positive things being said about AIX in this thread. I thought it was pretty terrible (my priors were SunOS, Solaris, HP/UX, IRIX, Linux, BSD). Personally, I preferred any of the above over AIX. AIX configuration was opaque with a windows registry style setup. All the standard utilities like sed, awk, etc., were versions from 1970. It was incredibly frustrating to use. They did supply some gnu software (IBM called it "linux" software), but it was managed through a second, separate, package manager, bare rpm. Decade(s) after every other nix had snapshots, the way to get a consistent backup on AIX was to break your boot disk mirror and backup the orphaned disk (while praying you didn't have a disk failure). Everything was spawned directly out of inittab. No sys-v/rc/etc. scripts. A hard down could break the journal on their filesystem rather than having the filesystem journal save your data. An fsck would not fix the journal. Most free software did not "just build and run" on AIX. Just about anything using autoconf required a custom wrapper around AIX's malloc to prevent it from segfaulting when being run, or fixing autoconf scripts to not mis-detect missing capabilities in AIX. AIX was not a first tier system for many vendors. I had to spend time in a debugger providing info to our SAN vendor on issues with their agent for AIX (we never had issues with their software for Solaris, Linux, or Windows). The hardware was funky. They did "neat" things like sharing a single CDROM drive between an entire rack of servers. But, to re-assign the CD drive, the IDE bus had to be re-assigned, as well as the PCI bus. And, invariably something would be blocking this, so "neat" in practice became a PITA. On the positives, AIX was stable once everything was dialed in, just like any other NIX. It was also trivial to create a bootable DR restore ISO for a system. And, their debugger was pleasant to use when diagnosing core dumps. "It used to be said that AIX looks like one space alien discovered Unix, and described it to another different space alien who then implemented AIX. But their universal translators were broken and they'd had to gesture a lot." -- Paul Tomblin

dosman33 4y ago
Sounds like perhaps like most of your experiences were with pre-AIX version 4? No system is perfect for sure. By the time I started using AIX it was with version 4 and was moving to 5 and I can't say any of the problems you've described were things I had encountered with it. Certainly I had lots of problems though. Not suggesting you didn't experience these things though of course.

neilv 4y ago

When the RS/6000 launched, AIX had some neat system management OS features and hypertext documentation that was better than any of the other workstation vendors at the time. Also, the RS/6000 and/or AIX was noticeably fast at some things. I remember a Systems Engineer being amazed that you could invoke a shell window (aixterm, IIRC), and it snapped instantly onto the screen, no lag.) The workstation vendors were often leapfrogging each other, but on that one metric, 0 perceptible time was new. I don't remember how compiles compared. If you can pick up an RS/6000 on eBay, with licenses and install media, it might be a little fun to play with. And maybe either check that GCC will work, or that you're getting license and media for the compiler. Today, though, there's so much neat stuff to play with atop Linux alone, that you could never get through it all. And, if you haven't already made your fortune and retired from paid work, things atop Linux are also more likely to be more directly relevant to paid jobs for current production environments, or at least to be better for resume keyword-matching.

yourapostasy 4y ago

If you have a pressing business need for near-mainframe security and/or resilience for monoserver applications, and are willing to spend the money for it, its hardware, staffing, and the platinum IBM Support and training, in some cases it is still cheaper than rolling your own under Linux. IBM packages a one-stop shop for a RAS experience [1] that would need a deep bench of engineering talent to reproduce were you to roll your own equivalent in Linux. So some customers would rather pay IBM than try to build such an organization and for them, AIX is worth it. Generally however with IBM’s rampant offshoring of support leading to a tremendous loss of institutional knowledge and rapid turnover of the offshore support teams, I’ve found unless you’re signing 7-9 figure renewal checks and paying for enhanced support, the support experience is way worse than it was around the 1990’s but still marginally better than other vendors. [1] https://www.ibm.com/downloads/cas/2RJYYJML https://www.ibm.com/downloads/cas/2RJYYJML