How the 60-Year-Old IRS Computer System Failed on Tax Day

Andreas Kohlbach

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Apr 15, 2019, 4:14:25 PM4/15/19

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The Youtuber LGR released a video today exploring, why the 60-Year-Old
IRS Computer System Failed on Tax Day 2018 in the USA.

To sum it up: even though using modern day hardware they emulate the old
IBM mainframes from back of the 1960s to run the old (COBOL and assembly)
code. And a well known bug not fixed caused almost the whole system to
fail.

Reminds me on the Y2K bug.

<https://www.youtube.com/watch?v=qL5ut8o5pfs>
--
Andreas

My random thoughts and comments
https://news-commentaries.blogspot.com/

Dan Espen

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Apr 15, 2019, 4:55:12 PM4/15/19

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Andreas Kohlbach <a...@spamfence.net> writes:

> The Youtuber LGR released a video today exploring, why the 60-Year-Old
> IRS Computer System Failed on Tax Day 2018 in the USA.
>
> To sum it up: even though using modern day hardware they emulate the old
> IBM mainframes from back of the 1960s to run the old (COBOL and assembly)
> code. And a well known bug not fixed caused almost the whole system to
> fail.
>
> Reminds me on the Y2K bug.
>
> <https://www.youtube.com/watch?v=qL5ut8o5pfs>

From that recounting, the bug was in the IBM DS8880.
Somehow, Unisys was in control of the hardware and they
declined to apply firmware updates.

I detect self destructive management behavior.

The complaints about not being able to support IBM COBOL and Assembler,
I think that's a lot of BS too.

--
Dan Espen

J. Clarke

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Apr 15, 2019, 8:34:22 PM4/15/19

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On Mon, 15 Apr 2019 16:14:24 -0400, Andreas Kohlbach
<a...@spamfence.net> wrote:

>The Youtuber LGR released a video today exploring, why the 60-Year-Old
>IRS Computer System Failed on Tax Day 2018 in the USA.
>
>To sum it up: even though using modern day hardware they emulate

Emulate? What leads you to believe that it's emulated? The
mainframes IBM makes today are direct lineal descendants of the IBM
360, implementing the instruction set in hardware not requiring an
emulator.

J. Clarke

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Apr 15, 2019, 8:42:04 PM4/15/19

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On Mon, 15 Apr 2019 16:55:05 -0400, Dan Espen <dan1...@gmail.com>
wrote:

Yeah, the problem clearly wasn't anything to do with "ancient
technology", the problem was with brand new modern hardware.

Dan Espen

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Apr 15, 2019, 9:50:10 PM4/15/19

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Looks like the DS8880 is from 2015, pretty new.
But the article says Unisys decided not to apply firmware updates.
So, not really a hardware issue. Not firmware either.
Someone was so afraid of change they removed IBMs ability to
apply field fixes. That kind of management can and does lead to
disaster.

--
Dan Espen

J. Clarke

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Apr 15, 2019, 10:32:14 PM4/15/19

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On Mon, 15 Apr 2019 21:50:05 -0400, Dan Espen <dan1...@gmail.com>

The point I was trying to make is that if the system had been written
in Go on Linux, the same failure would have occurred. The whole video
is going on about how old the software is when the age of the software
had nothing whatsoever to do with the failure.

Andreas Kohlbach

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Apr 16, 2019, 12:24:02 PM4/16/19

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On Mon, 15 Apr 2019 20:34:20 -0400, J. Clarke wrote:
>
> On Mon, 15 Apr 2019 16:14:24 -0400, Andreas Kohlbach
> <a...@spamfence.net> wrote:
>
>>The Youtuber LGR released a video today exploring, why the 60-Year-Old
>>IRS Computer System Failed on Tax Day 2018 in the USA.
>>
>>To sum it up: even though using modern day hardware they emulate
>
> Emulate? What leads you to believe that it's emulated? The
> mainframes IBM makes today are direct lineal descendants of the IBM
> 360, implementing the instruction set in hardware not requiring an
> emulator.

I have no knowledge of the whole thing. But if you watch the video at
around 9:00 LGR says so.

J. Clarke

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Apr 16, 2019, 5:20:08 PM4/16/19

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On Tue, 16 Apr 2019 12:24:01 -0400, Andreas Kohlbach

<a...@spamfence.net> wrote:

>On Mon, 15 Apr 2019 20:34:20 -0400, J. Clarke wrote:
>>
>> On Mon, 15 Apr 2019 16:14:24 -0400, Andreas Kohlbach
>> <a...@spamfence.net> wrote:
>>
>>>The Youtuber LGR released a video today exploring, why the 60-Year-Old
>>>IRS Computer System Failed on Tax Day 2018 in the USA.
>>>
>>>To sum it up: even though using modern day hardware they emulate
>>
>> Emulate? What leads you to believe that it's emulated? The
>> mainframes IBM makes today are direct lineal descendants of the IBM
>> 360, implementing the instruction set in hardware not requiring an
>> emulator.
>
>I have no knowledge of the whole thing. But if you watch the video at
>around 9:00 LGR says so.

I suspect LGR oversimplified the situation. Saying that the system is
emulated suggests that it is running on something like Hercules or one
of the official IBM equivalents. It's not, the code runs natively on
the silicon. What does get emulated is some of the storage devices,
but there again it's not like Hercules where the emulated storage
device is a file on a disk on a PC, the emulator is a hardware device
that is attached to the mainframe using the mainframe's proprietary
interfaces, which hardware device responds as if it is a different
hardware device--so a device will appear to the computer as if it is a
channel controller running a bunch of tape drives, when it's really a
channel controller running a bunch of disks, with some firmware that
does the necessary command remapping. The emulation in effect takes
place downstream of the channel controller.