* Posts by Lysenko

986 publicly visible posts • joined 23 Jan 2015

ServiceNow unleashes its 'Kingston' release

Lysenko

Re: Service Now

Well, they named this release after "Hull on Earth" so they can be credited with some (unintentional) oblique honesty.

Let's Encrypt plugs hole that let miscreants grab HTTPS web certs for strangers' domains

Lysenko

With an HTTP-01 challenge, the client (cert requester) has to prove it controls HTTP (Port 80) for the domain. With TLS-SNI-01 it only had to prove it could reply from the same IP address as the domain.

'Mummy, what's felching?' Tot gets smut served by Android app

Lysenko

It's just as well children don't remember the birth process...

I mean, there's some pretty gruesome and explicit stuff going on there in glorious, technicolour close up. Given the catastrophic effects of such images on young minds (allegedly), any child with a prematurely active visual and memory system would probably never recover!

Next; tech; meltdown..? Mandatory; semicolons; in; JavaScript; mulled;

Lysenko

Re: Anyone seen a single line C program ?

Actually, after 20 years of Java threading I'm coming around to the JavaScript everything-is-a-callback idea.

After 20 years of Java threading[1] one appreciates why GoRoutines were invented (or Erlang).

[1] Not that I've ever used Java in anger, but you can lose yourself in semaphore/mutex hell with C++ as well, which what I'm assuming you're referring to. Node/JS is equivalent to tackling flu by mandating mouth breathing and abolishing noses - you can always eat dinner with a callback after all.

Lysenko

Re: Anyone seen a single line C program ?

That was common with xBase libraries and it's ubiquitous with JavaScript (uglfiy.js etc) because compressing out whitespace and converting variables to single characters reduces the size of downloads (bogus argument of course since you can just gzip the un-obfuscated source and any browser too retarded to support gzip isn't going to support ES5/CSS3 reliably anyway).

The key to success with JavaScript and it's tooling is realising that when you think:

"I'm missing something. It can't be this retarded. Turbo C/Visual Basic/Delphi was more advanced 20 years ago!?"

... you're wrong. It really is that retarded and the browser programming model really is Win16 redux, complete with message queues, async API callbacks, state machines a-go-go and no threading worth a damn. With ES8/TypeScript and web workers (threads) the JS eco-system might catch up to Delphi 3 on WinNT 4 by 2025 - maybe - but don't count on it.

[*] I've just spent 3 months writing an Angular 4 system so I'm not just ranting from the sidelines.

Lysenko

Berlin-based developer Yoshua Wuyts laments

Berlin-based hobbyist, I think you mean. I have never met a developer who only used a single language, except for some embedded guys who do everything in C (and even they know several ASM flavours). If all you know is JS then you're equivalent to a VBA power user writing Word macros, which is a useful skill but doesn't give you a credible perspective for addressing language design issues. Listening to guys like this is how Personal Home Page managed to become and remain the worst language in the world (tm).

And it, feels, well, a little hurtful."

Get used to it, snowflake. You're dealing with computers here. They don't "do" empathy and they don't give an Aardvark's left testicle about your emotional state.

What do we want? Consensual fun times. How do we get it? Via an app with blockchain...

Lysenko

Re: What One Desires.....

I want a 100% monogamous sexual relationship, ... Is this possible

.....

You betcha. I have had that exact arrangement for the past 6 years.

If your consent to this sexual relationship is predicated on the "100% monogamy" clause then should your partner have an affair without your knowledge, that renders any subsequent sex with you non-consensual and therefore "rape" under current "zero critical thinking tolerance" criteria.

In fact, it's rape on two grounds (fraud and by proxy) as well as reckless endangerment while owing a duty of care, which is a pretty profitable area of tort. Lawyers in the bedroom - lovely.

Lysenko

I've seen some stupid ideas in my time but that's ridiculous and wrong on so many levels it'll probably be a success.

I couldn't agree more, but enough about FaceBook ........

No wonder Marvin the robot was miserable: AI will make the rich richer – and the poor poorer

Lysenko

Re: AI is irrelevant

potentially past my aforesaid cliff edge.

Which is when (after some violence) you return to the historically "normal" state of affairs by re-instituting slavery or indentured servitude or workfare or dictatorship of the proletariat or whatever other euphemism you choose for compelling people to do more work than they want to do for less pay than they want to receive.

Until we achieve Culturesque freedom from resource constraints, achieving equality and the aspirations of all it will always be unsustainable because classes and hierarchies are integral to any functioning social system. Taken historically, the current levels of wealth equality in the western world are unprecedented. Rome, for example, had Marcus Licinius Crassus on the one hand (probably the richest man who ever lived) and chattel slavery on the other.

Lysenko

Upstairs, Downstairs

That's where humans have an (currently) unassailable advantage. Roombas are impressive in a limited sense, but they are a hopeless joke compared to a wetware cleaner. Same for all the IoT doorbells and thermostats: they're no threat to the capabilities of a proper Footman and Butler. Maybe we'll end up 150 years in the past when a middle-class job like Bank Manager (i.e. Network Sysop) was expected to support half a dozen full-time jobs back home.

Beer hall putz: Regulator slaps northern pub over Nazi-themed ad

Lysenko

I think the problem is it was described as a German night, therefore equating Germans with Nazis.

It isn't uncommon (particularly on the wrong side of the pond) to equate Russians with "Commies" without giving everyone the vapours and lots of Vodka branding relies on either Romanov or Soviet stylistic cues.

Couple that with the Holodomor (deadlier than Hitler's effort all by itself) and the other 50-70M wiped out by the Sino-Soviets and I sense a double standard.

Hitler's superlative sin was murdering so many white, western Europeans. His Communist colleagues mostly stuck to murdering easterners and "Asians", so Hitler gets promoted to be the head of the axis of evil rather than number three where he belongs.

Lysenko

Replaced Nazi with black or jew in the original article and see if you can figure it out yourself.

Nazis aren't a racial group. Try replacing "Nazi" with "Soviet" or "Maoist" and see if you can figure it out.

Hold on to your aaSes: Yup, Windows 10 'as a service' is incoming

Lysenko

Re: Who didn't see this coming?

I don't down vote often, any more, but I think that is very naive and got one.

Naivety doesn't really come into it. You assume that Microsoft either have no interest in retaining their position as the most popular desktop OS or they are terminally incompetent - and I'm not convinced of that. I don't actually care one way or the other since most of my machines run Linux anyway.

Some of the reactions one gets around here lead me to think that a malaria vaccine (should one be created) will be dismissed as an evil innovation if it turns out Bill Gates (Boo!! Hiss!!!) had a hand in funding it.

Lysenko

Re: Who didn't see this coming?

I wonder how long it'll be before there's a monthly subscription charge...

Hmmm. Build in and then enhance a Linux subsystem (thus getting an open source competitor into places it otherwise wouldn't be) when your end game is to increase charges?

Sorry, I don't buy it. That's too dumb even for Microsoft. I'm sure there is an end-game, but it's not going to be that.

SAP customers won't touch the fluffy stuff... so here's another on-prem HR data tool

Lysenko

A more likely explanation is that the cloud isn't ready for GDPR, nor will it be. In the meantime, can whoever coined the phrase "human capital"

If they were honest and said what they mean (Livestock Tracking) they could probably get around GDPR by claiming it is a Common Agricultural Policy requirement.

Meltdown, Spectre bug patch slowdown gets real – and what you can do about it

Lysenko

Or chuck out their current CISC infrastructure and switch over to a RISC-based one? (unlikely).

Given that we know ARM is impacted by these security flaws as well, the CISC/RISC calculation remains unchanged - unless you're suggesting they port the whole of AWS to MIPS.

Your connection is not Brexit... we mean private: UK Tory party lets security cert expire

Lysenko

"Your connection is not private."

That's not an error message, it's a Home Office policy announcement.

Wait! Before you fire up that HP lappy, check the battery

Lysenko

Now do you get it?

This is the sort of thing "Mugabe" Meg was afraid of over on the other side of HP. Making things is almost as dangerous (to C suite bonuses) as employing people in jurisdictions that have the concept of employment law. Far better to abandon this last century concept of "products" and concentrate on real estate deals with surplus factories, warehouses and offices. In C21 it's all about being a "brand" rather than a "product".

Windows Store nixed Google Chrome 'app' hours after it went live

Lysenko

Re: I use Linux

@MacroRodent

but someone now coming from Windows will have no problem finding GUI editors with UI essentially indistiguishable from typical Windows editors

If you're coming from Java riddled monstrosities like Eclipse and (for a lesser value of monstrous) IntelliJ then I'd agree with you, just like OpenOffice on Windows is just as bad as the Linux version. I'm not discussing cross-platform lowest common denominator-ware though.

In any case, I don't need to "come from" Windows. All my dev work is Linux or bare metal already and I have three Linux dev machines and one Windows (VMs complicate hardware interfaces). I don't need to "see the light". I've been using Linux for years (xcfe-Mint, CentOS and Yocto, mostly) and I know exactly what it is capable of.

Today, for example, I was doing web stuff. Linux has no answer to either PhotoShop or Illustrator, even if we set the coding aside. How do I know that? Because I just spent half the day in Gimp and Inkscape. The issue isn't that I'm unaware of Linux tools or unable to use them. It is that I am aware, can use them, do use them - and judge them to be inferior in most cases (PCB CAD being an exception).

Lysenko

Re: @Lysenko - I use Linux

If the only editors you know are Vim and Emacs then I strongly doubt you've ever really used Linux.

What did you have in mind? Geany? GEdit? Atom? I already mentioned I use IntelliJ (also the Pycharm and CLion variants) for some things and consider Eclipse to be a bad joke. VSCode? A pale shadow of the real thing (better than Atom though).

Lysenko

Re: I use Linux

I write software for Linux and embedded microcontrollers - on Windows. I have three physical Linux machines (not counting servers) and any number of VMs, but 90% of my work is conducted on Windows[1], even though I haven't deployed anything on that platform for half a decade.

This isn't really relevant to the discussion either, but it (hopefully) might enrage a fanboi or two.

[1] Because: Visual Studio ... and yes I know about VSCode and I have a JetBrains subscription I use for Kotlin. Vim or Emacs? I'd rather change career. Eclipse? Hahahaha ...yeah ...right after I start developing in PHP ... or Visual FoxPro.

Republican tax bill ready to rescue hard-up tech giants, struggling rich

Lysenko

Re: I don't get it

Dude, are you aware of how many trillions of dollars were added to the US debt during the last admin? I'd guess not, or you wouldn't make such an asinine comment.

Also, when an economy grows the debt shrinks, something that NEVER happened under Obama...

You walked into a lamp post yesterday so you are obliged to do so again today because ... precedent? Tradition? Bone-headed stupidity?

You're so locked into your little dichotomy that you assume that everyone who criticises Republican legislation must be a Democrat and consequently a supporter of the Obama Executive, even though the Executive branch isn't empowered to control taxation and spending (other than vetoing it) which makes Obama (and Trump) essentially irrelevant in this context..

Democrats want to borrow and tax so that the government can spend whereas Republicans want to borrow and cut tax so that the electorate can spend. What if you're a fiscal conservative? What if "borrow" is the consistent feature that concerns you so you want to both cut spending and raise taxes? Too complicated, right? Reasoned analysis be damned. All we need to know is whether Satan Obama would approve and that determines which side we're on.

Lysenko

Re: I don't get it

Isn't having 2.2% more income great for EVERYBODY?

Not if you're doing it by taking out loans that the following generation of taxpayers are going to have to pay for. It's quite ironic that (many) Republicans are fixated on the "rights of the unborn" except when it comes to adding over $1T to the deficit tomorrow so they can party like drunken sailors on their golf courses today.

Facebook flashes ramped-up face-recog tech. Try not to freak out

Lysenko

"...or reach out to the person who posted the photo if you have concerns about it"

I'm only likely to "reach out" to someone if I intend to grab them by the neck - for example, in the case of people using the expression "reach out" when they mean "contact", "ask", "email" or "speak to".

Fridge killed my baby? Mag-field radiation from household stuff 'boosts miscarriage risk'

Lysenko

...and lack of Pirates causes global warming.

This is a human study in California so exposure to high MF/EMF levels may directly correlate with exposure to known carcinogens and other noxious chemical compounds from internal combustion engines and other industrial processes. You can't just wave your hands and declare that "we've controlled for those factors". It isn't possible to control for that just by slapping a dosimeter on volunteers and then plotting exposure against outcome.

To move beyond "Daily Mail Headline" they need to map exposure to all the other environmental factors and then devise some means of excluding any potential effects their effects. As it stands they're essentially asserting that close exposure of the nose to naked flames elevates the risk of lung cancer.

Top Silicon Valley tech judge hits alt-F4 under cloud of sex-pest claims

Lysenko

Re: where people are treated fairly and equally

ok you young whippersnappers probably don't know who that guy is...

Just to elaborate (because it was a long time ago), "Henry Kissinger" is/was a satirical caricature, based on a well known National Security Adviser named "Dr Strangelove". As with most caricatures, Kissinger was an exaggerated parody that amplified the reactionary, amoral, untrustworthy and warmongering aspects of Strangelove's character for (very) black comedic effect. Apparently, much as with Ali G and Borat, many prominent people were taken in by Kissinger and mistook him for a genuine foreign policy adviser, causing something of a dilemma for the scriptwriters who had assumed the insanity of their creation would be obvious to everyone.

Peak smartphone? iPhone X flunks 'supercycle' hopes

Lysenko

Re: The "Horned One"

When you mentioned horns the first thing that came to mind was the Irish Elk.

One theory regarding the extinction of this creature is that it invested so many resources into showing off with ludicrously expensive status symbols with no added utility that it undermined its ability to compete and survive. Close relatives with more sensibly sized (and priced) status symbols are with us to this day. Darwin is always watching; Fanbois.

'I knew the company was doomed after managers brawled in a biker bar'

Lysenko

Re: It's all fun and games until someone's toes freeze solid and shatter,

in the days before H&S and political correctness spoiled everything

I still remember the name of one my chemistry compatriots who refused to believe that the pencil sharpeners were made from blocks of magnesium and decided to prove us wrong with the help of a bunsen burner. It made a terrible mess of the teacher's desk on the level below. After burning its way through the floor ;)

No hack needed: Anonymisation beaten with a dash of SQL

Lysenko

Re: How about the use of Cascading Temporal Surrogate Keys?

Screen scrape the data and then store it offline keyed on a hash of the non-key fields. You then have a stable PK for each logical tuple and can track key collisions in a counter field (assuming some denormalization in the source).

The entire concept is flawed. If you have enough attribute data regarding an entity then it will always be possible to resolve the PK in any quasi-normalised dataset because the corollary of a tuple being dependent on "the key, the whole key and nothing but the key" is that the key is dependent on the attributes and for any reasonable dataset, some of those attributes will have high cardinality.

Lysenko

I had another idea, put the data online and let the public enter search parameters to find themselves to show them how easy it is to re-identify, then prompt them to write to their MP.

How about putting the complete medical, financial and educational records of all MPs online, after running it through the officially approved anonymisation process. If no-one has managed to reverse that back to individual identities inside maybe 6 months then maybe it's safe to try it out on the general public?

Oi, force Microsoft to cough up emails on Irish servers to the Feds, US states urge Supremes

Lysenko

Re: Yeah, but common sense, too...

Not quite. GDPR as it stands also applies to personal data stored in the EU about natural persons residing outside the EU.

Under a plain reading of Recital 14, yes however that is subject to the provisions of Art. 2 S2(a) which provides limitations and Art. 3 S1 which is ambiguous in terms of the interpretation of the word "establishment" due to the second clause of the sentence. This sort of thing will take case law to clarify so, as things stand, one can only be certain that GDPR protects the personal data of persons resident within or citizens of the EU in the context of activities taking place within the jurisdiction of the ECJ (Art. 2).

Lysenko

Re: Feral Criminality

C) They resent the implication that American law and Judicial fiat lack universal jurisdiction and feel the need to reiterate that the "sovereignty" of other countries is a privilege granted by the USA rather than a fundamental right and therefore exists only so long and as far as the USA condescends to permit it.

Lysenko

Re: Yeah, but common sense, too...

Well in the case of the EU it would be because personal data stored in the EU is protected under the GDPR regulations,

Not quite. GDPR applies to the personal data of EU citizens or resident immigrants. It does not cover foreign nationals or transient visitors so emails belonging to an American citizen/resident stored in Ireland are outside the scope of GDPR.

Facebook confesses: Facebook is bad for you

Lysenko

Facebook is depressing?

In other news, bears, Popes, woods, Catholicism.

This isn't about smelling coffee, it's about noticing you've been living next door to a malfunctioning sewage works for a decade.

Microsoft's 'Surface Phone' is the ghost of Courier laughing mockingly at fanbois

Lysenko

Re: Too late

SatNad should move over to TomTom or Garmin. He'd fit in better.

A million UK homes still get crappy broadband speeds, groans Ofcom

Lysenko

Re: I'm not rural

I'm not rural

I live a 20 minute commute from a major city

We have an office 20 minutes commute from a major city and it most definitely is rural. The speed there is frequently around 2Mbps and cellular is even worse. Only O2 is even vaguely stable.

I'd like to moan about this, but it would be a bit disingenuous. The speed we get is fine for C&C of cloud VMs and BT Infinity back home (in the city) is both fast and stable. I'd be screwed if I lived within walking distance of the office though (like the local school).

Erase 2017 from your brain. Face ID never happened. The Notch is an illusion

Lysenko

Re: Old fashioned?

I can also get my wife to unlock it if needed - e.g. when I'm driving and need to reply to a message or suchlike. I'm just not seeing where the great benefits of biometric locking lie.

That's because you're not cheating on your wife or, if you are, you're smart enough to use a burner phone for that sort of thing. Others, however......

Lysenko

Re: Prefer authentication on the front of the phone

Agreed. If I'm picking up my phone my fingers are on the back of the case, not the front. How is obscuring the display by slapping your fingers over it supposed to be preferable? It defies ergonomics. The only time a front sensor would make any sense if the phone was face up on a desk and I didn't want to pick it up, which doesn't happen because how am I going to do anything useful with it in that position?

FCC douses America's net neutrality in gas, tosses over a lit match

Lysenko

Re: Sorry to be parochial (or perhaps actually 'cosmopolitan')...

Well there's that, but there's also: the US is one of the biggest sources of and markets for internet services. It's not like only Americans use Netflix or Amazon video, is it?

True, but it's not like they've got the population of Europe either (let alone China and India) and they're not likely to close that gap given that all US discussion of immigration revolves around limiting it rather than promoting it. That places a hard upper limit on the extent to which America influences global decision making.

I agree that Google and Amazon etc. have the sort of reach that makes their decisions relevant on a global scale, but American cable companies? They'll doubtless use their de facto regional monopolies to fleece customers via packages and premium services, but as one of the ACs pointed out - elections have consequences.

Replicating that here would take primary legislation rather than regulatory tweaks and the only beneficiary would be OpenReach so they would be opposed by literally everyone else in the industry, not just the public.

Lysenko

Re: Making the Internet Great Again

As far as I can make out, too, "Big John"'s posts are like the articles in Pravda in which everything that was happening had to be referred to the doctrinal errors of the currently out group

Agreed. It's nostalgic to see such unshakeable ideological partisanship making a comeback. For the resurgent right wing, everything (and I do mean EVERYTHING) that carries the taint of Obama must be expunged and his (imagined) cult of personality dismantled. Meanwhile, the fuming left wing is busily rehabilitating GWB since nothing (and I do mean NOTHING) could possibly be worse than the current administration.

What is a bit different is in the Soviet era there was the possibility of error or well-intentioned policy with ultimately negative effects. That doesn't exist on either wing of American politics. Everything and everyone is either "good" or "evil" and anything occurring under an "evil" administration must itself be evil. If the Soviets worked the same way, Kruschev wouldn't just have denounced Stalin - he would have deindustrialised the country to erase his legacy.

Lysenko

Sorry to be parochial (or perhaps actually 'cosmopolitan')...

... but does this matter outside the USA? I guess it allows them to throttle a foreign video streaming site and make the American market a de facto YouTube monopoly, but essentially it already is and anyone working at scale would likely use local AWS anyway. Am I missing something, besides the symbolism of the precedent?

Funnily enough, no, IT admins who trash biz machines can't claim they had permission

Lysenko

Re: This man is obviously a psychotic

I think at least some of these cases can be explained by a little rephrasing:

"There's no excuse for any employer to damage an employee's livelihood, either directly or in terms of agreed benefits. As an employer, you have been given a great deal of power and a high level of dedication, at the very least show a reciprocal degree of loyalty to show you deserved that trust the employees placed in you."

Years of treating people as "Human Resources" (i.e. objects to be exploited) causes some employees to adopt the same mindset. From this point of view, the employer is simply an ore-bearing seam that the employee mines to extract resources to further overall career objectives. Obviously, you don't deliberately collapse your own mine while it is profiting you, but once it's worked out, all bets are off. You don't show "loyalty" to a hole in the ground. It certainly isn't going to show any to you.

Lysenko

Re: This man is obviously a psychotic

The man is obviously an idiot. With his level of access, he could have just leaked remote credentials to certain murky corners of the internet and retained bulletproof deniability while l33+ hax0rz trashed the system for him.

IETF protects privacy and helps net neutrality with DNS over HTTPS

Lysenko

Re: @Lysenko Now this would be a great idea...

The reason public key cryptography was invented was to remove the burden of distributing one-time pads.

I'm aware of that, however, for some use cases, OTP distribution isn't a significant problem. However, a perpetual problem with IT security is cargo culting "best practices" without really understanding them and imagining that it eliminates the need to model your attack surface and threat environment. Sometimes TLS/RSA/AES isn't the best answer[1] and "roll your own" encryption can be a superior solution.

[1] IoT leaf nodes, for example. You often don't have the MIPS, RAM or power budget for anything like TLS but you might have enough flash to store an OTP large enough to last for the battery lifetime of the unit.

Lysenko

Re: Now this would be a great idea...

That's also your weakness. The recipient of a message also needs a copy of the pad. That means that you have to have a secure method of distributing the pads.

Oh, I agree, but if you're establishing any sort of long-term relationship with the peer then there are established mechanisms for that just as there are for distributing physical credit cards. In my case, they're remote SBCs programmed by me and then deployed in the field.

Lysenko

Re: Now this would be a great idea...

Don't ever try and invent or write your own implementation as you're almost guaranteed to get it wrong.

That depends on the value of "wrong". All commonly used industry standard encryption is "broken" in a mathematical sense. It is fully deterministic and the maths needed to break encryption keys is mostly a solved problem (factoring primes etc). It is the *scale* of the problem that provides the security, not the principle.

I've knocked up algorithms and implementations for fun and one of them is actually in use for live data (again, for fun). I am certain that the NSA is closer to cracking AES than they are to cracking my cypher, not because of the quality of my code or my maths ability, but because one time pads cannot be broken except by resolving the random number generator that created the pad and that isn't feasible retrospectively for a pad generated from RF static.

Once you have a secure pad, you can implement your own substitution cypher pretty much any way you like and security isn't compromised in any way. If I were directing anything criminal I would issue my confederates with 128Gb USB sticks full of random noise and cease to worry about spying. The only way to break in is to get a copy of the pad and that is the exact same problem as getting a copy of any other password that is too long to memorize (that's all an OTP is after all - a giant password).

Checkmate: DeepMind's AlphaZero AI clobbered rival chess app on non-level playing, er, board

Lysenko

Let's be realistic...

What is this stuff for? What is Google for? This isn't about playing chess or helping people search the internet, it's about advertising. Google is an ad delivery network that uses a search engine as bait and this AlphaZero thing is an ad delivery optimisation engine that just so happens to be able to play chess as a side effect.

On that basis, it is perfectly understandable that Google refuses to publish all the test data. Sophistry, mendacity and psychological manipulation are the pillars on which the advertising industry stands. Criticising an ad firm for being economical with the truth is like criticising the sea because you can't drink it.

No one saw it coming: Rubin's Essential phone considered anything but

Lysenko

£100 more than a Samsung S8... ???

... and it isn't an iPhone? Of course it isn't selling. It needs to be RRPed at the psychological £499 price point and then promotion discounted from there if they want to get any traction.

(Amazon UK prices)

Kaspersky dragged into US govt's trashcan as weaponized blockchain agile devops mulled

Lysenko

A modern person who knows about Attainder: a nasty little law that was extensively used during the Deformation to steal land from people who disagreed with the ruling elite. So your calling of the similarity is striking - as is the observation that the alleged crimes of the company are unprovable religious dogmata.

There's nothing religious or obsolete about attainder where US law is concerned. The "Elizabeth Morgan Act" was struck down on that basis in the early 2000's and the Holman Rule is an example (re)activated only this year.

Pickaxe chops cable, KOs UKFast data centre

Lysenko

Re: DR Testing Failure

If the UPS is sized for the few minutes during which the generators are supposed to get their act together you might have maybe 30 degrees rise before the power fails, so not yet tripping overtemp safeties.

The problem with that is that the UPS sizing is always based on full DC capacity whereas a cold aisle containment unit is a semi-sealed micro-climate. That means that in a part filled DC it is possible for a given CAC unit to keep on trucking for several times longer than the design calculations suggest and ambient cooling doesn't help because the CAC is semi-sealed. In the case I referred to above, the equipment was still operating on UPS at least half an hour after HVAC went down.