Reply by a a December 9, 20232023-12-09
The idiot not@telling.you.invalid (Computer Nerd Kev) persisting in being an Off-topic troll...

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not@telling.you.invalid (Computer Nerd Kev) wrote:

> Message-ID: <65738a98@news.ausics.net> > From: not@telling.you.invalid (Computer Nerd Kev) > Subject: Re: cheap usb ("thumb") drives > Newsgroups: sci.electronics.design > References: <uk8317$v4vl$1@dont-email.me> <slrnumflkc.v1f.dan@djph.net> <uk9pjr$1b0dt$1@dont-email.me> <uk9udg$1boju$3@dont-email.me> <7054764f-b65c-4117-aacb-38ddae96ba01n@googlegroups.com> <uka2gn$1cefq$2@dont-email.me> <uka46v$1cnfc$1@dont-email.me> > User-Agent: tin/2.0.1-20111224 ("Achenvoir") (UNIX) (Linux/2.4.31 (i586)) > NNTP-Posting-Host: news.ausics.net > Date: 9 Dec 2023 07:28:57 +1000 > Organization: Ausics - https://ausics.net > Lines: 17 > X-Complaints: abuse@ausics.net > Path: not-for-mail > X-Received-Bytes: 1580
Reply by john larkin December 8, 20232023-12-08
On Fri, 1 Dec 2023 11:08:12 +0000, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:

>On 30/11/2023 12:15, Don Y wrote: >> On 11/30/2023 3:53 AM, Martin Brown wrote: >>> On 30/11/2023 00:24, Dan Purgert wrote: >>>> On 2023-11-29, Don Y wrote: >>>>> I've got a box that builds a "backup partition" on a machine >>>>> and then invokes it to install the OS/apps prior to distribution. >>>>> >>>>> Some of the clients are hosing the backup partition by trying to >>>>> upgrade to Windows, etc. >>>> >>>> Not your problem if they trash their box, is it? >>> >>> It might be. >> >> If your (paying) customer trashes the item he BOUGHT from you, >> do you tell him to go suck eggs because he mistreated it? >> How much responsibility can he heap on you for creating a >> product that was so EASILY mistreated? > >Depends on what you mean by easily. Few devices with spinning rust in >can survive being dropped 3' onto a concrete floor, iPads and mobile >phones are even more fragile. My old one had a bit missing from its >"Indestructible" gorilla glass but still worked. My wife had someone >drop an iPad destroying it beyond economic repair. > >> Even if you refuse to comp him for his losses, do you, also, >> refuse to do any further business with him? > >Potentially. We took to putting telltales into the shipping package >after one damaged machine came back with clear evidence that it had >stood upside down in 12" of salty water long enough for mild steel parts >to go rusty. That pretty much clinched who was at fault (it was the sort >of kit that is shipped in air floatation supports "this way up!"). > >Most spectacular one to repair we ever had was when they dropped one >from the cargo bay door of a 747. It was never the same again. >> >> When your customer doesn't give you monies for your product, >> the dynamics change!&#4294967295; ("You've been a bad boy!&#4294967295; We're going to >> cut our ties to you...") > >Absolutely. I had a strict policy of no support for existing work until >my bills were paid. Some of the large companies I worked for as an >employee and then later as a contractor would only pay their bigger >bills when someone from the bailiffs turned up to take the fax machine >away. I knew their systems and MO so I made damn sure that I got paid on >time and in full.
One of my aerospace customers sometimes expresses concern that we aren't making enough money. We shipped a bunch of VME modules with a bug. They said "you're a small company, let us pay you to fix it." We declined the offer. On the other hand, companies in Silicon Valley tend to be cheapskates and steal our IP when they can. Different culture.
Reply by Computer Nerd Kev December 8, 20232023-12-08
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:
> If your laptops have full size SD card slots, you could use micro-SDs with > adapters. > > Lots of adapters have a "read-only" switch, and that plus a drop of epoxy > seems like a reasonable solution.
A better approach for SD/MicroSD cards is to set their controller to read-only mode, which can be permanent. I'm not sure whether any normal card readers (or their public drivers) support this, but there are dedicated devices for doing it: https://blog.tindie.com/2021/02/sd-card-locker/ -- __ __ #_ < |\| |< _# | Note: I won't see posts made from Google Groups |
Reply by whit3rd December 6, 20232023-12-06
On Wednesday, December 6, 2023 at 3:23:29&#8239;AM UTC-8, Martin Brown wrote:
> On 01/12/2023 20:29, Don Y wrote: > > On 12/1/2023 4:08 AM, Martin Brown wrote: > > >> Another simple option would be a write once CD and then you could > >> include images for a few different machines on one disk. That way any > >> copy of the right CD will do to make a trashed machine work again. > > > > Machines are now being offered without optical drives. ...
> If they have a full size sD slot then I favour Phils suggestion of a > micro sD in an sD carrier write protected with a spec of araldite.
That's weak, though. The 'write protect' of the carrier is just a suggestion, not hardware-implemented, but sets a bit that can be polled. Or, ignored. The SD specification does include non-reversible write disable commands (and the SD card control logic will never enable the voltage boost necessary to write new data into the flash). That, IS a hardware write protection. Check out the Wikipedia on SD card, there's references... <https://en.wikipedia.org/wiki/SD_card>
Reply by a a December 6, 20232023-12-06
The idiot Don Y <blockedofcourse@foo.invalid> persisting in being an Off-topic troll...

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Don Y <blockedofcourse@foo.invalid> wrote:

> Path: not-for-mail > From: Don Y <blockedofcourse@foo.invalid> > Newsgroups: sci.electronics.design > Subject: Re: cheap usb ("thumb") drives > Date: Wed, 6 Dec 2023 09:40:34 -0700 > Organization: A noiseless patient Spider > Lines: 95 > Message-ID: <ukq867$rar5$2@dont-email.me> > References: <uk8317$v4vl$1@dont-email.me> <slrnumflkc.v1f.dan@djph.net> > <uk9pjr$1b0dt$1@dont-email.me> <uk9udg$1boju$3@dont-email.me> > <ukcer9$1rga1$1@dont-email.me> <ukdfn5$20ktn$2@dont-email.me> > <ukplfo$o6ce$1@dont-email.me> > MIME-Version: 1.0 > Content-Type: text/plain; charset=UTF-8; format=flowed > Content-Transfer-Encoding: 8bit > Injection-Date: Wed, 6 Dec 2023 16:40:39 -0000 (UTC) > Injection-Info: dont-email.me; posting-host="f12cc54faa5c951b8e84bd25435b3f14"; > logging-data="895845"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18wtb3NOervENM6Ib64LudJ" > User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:102.0) Gecko/20100101 > Thunderbird/102.2.2 > Cancel-Lock: sha1:H/Bu8uY8dQs93CPue/4uJXqeEz8= > Content-Language: en-US > In-Reply-To: <ukplfo$o6ce$1@dont-email.me> > X-Received-Bytes: 5731
Reply by Don Y December 6, 20232023-12-06
On 12/6/2023 4:21 AM, Martin Brown wrote:
> On 01/12/2023 20:29, Don Y wrote: >> On 12/1/2023 4:08 AM, Martin Brown wrote: > >>> Another simple option would be a write once CD and then you could include >>> images for a few different machines on one disk. That way any copy of the >>> right CD will do to make a trashed machine work again. >> >> Machines are now being offered without optical drives.&nbsp; I think the design >> rationale is that you can access RUNTIME media via the network connection >> and boot media via USB devices. >> >> This is especially true for smaller machines (which are a favorite of >> the clients because they don't want to have to lug something with a >> 17" display) > > If they have a full size sD slot then I favour Phils suggestion of a micro sD > in an sD carrier write protected with a spec of araldite.
I don't have a say in the machines we are gifted. And, the clients *technically* don't have a say in the machines that we give *them* (though we try to accommodate). The homemade restore partition was a win because it could be made to work (function) with any laptop that had a keyboard and a boot disk. The problem was that there was no easy way to protect it; Joe Average could clobber the image in an attempt to install a new OS.
>> [I have a pair of netbooks, here, that I keep because they *are* >> so small.&nbsp; I can slip them BOTH in a desk drawer instead of having >> to store them on a shelf in a laptop bag.] > > My favourite portable for travelling is an ASUS T1000 (not made of liquid > metal) 11" diagonal screen. It's not fast, a bit long in the tooth now but > lasts a long time and is very small. It even comes apart so that you can use > the screen as a tablet.
I used to have a tiny Sony laptop. All of the I/Os were on a dock (save for USB and a memory stick). Including the optical drive, printer port, etc. I could leave that at home and have this slim little device that didn't weigh down my carry-on -- the power adapter weighed more than the "laptop" (I carry a fat briefcase with laptop and a few changes of clothing inside so ALL my luggage fits under *my* seat). The keyboard was small/cramped (I like a full size keyboard) but I mainly used it to check mail and run demos. It's gone, now -- one of my "purges" (I have a shitload of kit!). Now, I carry an aircraft carrier. Impractical for use on planes but 17" screen and full-sized keyboard make a difference in use.
>>> Or even the micro CDs that come with drivers on. >> >> I've been exploring UEFI BIOSes (for another project) with the goal >> of making a machine unusable as a generic PC (prevent the OS from >> being installed).&nbsp; If this bears fruit, I may be able to take some >> information from that and use it to cripple these machines to >> protect the HPA and boot record (e.g., block writes to any of >> those areas so an OS install throws an error) > > That sounds like hard work for little gain. BIOSes can also be overwritten.
I have no desire to write any code. Rather, just juggle entry-points (function bindings). So, when COTS (or FOSS!) software tries to "write to display", the code that executes is "read from keyboard". Etc. This will allow me to leave the initial boot code in place but cripple any efforts of any other software that EXPECTS an ISA BIOS. My OS, OTOH, just needs to rearrange the hooks to the machine's modified BIOS to take into account this new mapping. ANYTHING that I do can be undone. But, you have to know what has been done and how to undo it. Try to boot some other installer and the machine will appear to lock up. Reboot the *native* OS and all works fine. (I.e., the machine isn't broken; just the foreign installer!) What we're trying to do is prevent the sort of things that have happened with folks trying to "repurpose" the machine for some other "mainstream" use. E.g., bring it to a pawn shop and it won't RUN like a "PC". Their staff won't be able to install a new OS so they quickly realize they have a brick (and won't buy any other similarly "marked" machines. The machines aren't particularly valuable (we get them for free). But, we want to be able to control the machines LOANED OUT (for this program) so they are all identical. *And*, encourage them to come back to us (on completion of the program, each participant is gifted a "real" laptop).
Reply by a a December 6, 20232023-12-06
The arsehole Martin Brown <'''newspam'''@nonad.co.uk> persisting in being an Off-topic troll...

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Martin Brown <'''newspam'''@nonad.co.uk> wrote:

> Path: not-for-mail > From: Martin Brown <'''newspam'''@nonad.co.uk> > Newsgroups: sci.electronics.design > Subject: Re: cheap usb ("thumb") drives > Date: Wed, 6 Dec 2023 11:21:28 +0000 > Organization: A noiseless patient Spider > Lines: 41 > Message-ID: <ukplfo$o6ce$1@dont-email.me> > References: <uk8317$v4vl$1@dont-email.me> <slrnumflkc.v1f.dan@djph.net> > <uk9pjr$1b0dt$1@dont-email.me> <uk9udg$1boju$3@dont-email.me> > <ukcer9$1rga1$1@dont-email.me> <ukdfn5$20ktn$2@dont-email.me> > MIME-Version: 1.0 > Content-Type: text/plain; charset=UTF-8; format=flowed > Content-Transfer-Encoding: 8bit > Injection-Date: Wed, 6 Dec 2023 11:21:28 -0000 (UTC) > Injection-Info: dont-email.me; posting-host="5d562caf615562cc57f78d951ae12a41"; > logging-data="792974"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19okm1LovpYfnO1o9+e5KhB2JGMXBXdwhsDIOEPH0PWsA==" > User-Agent: Mozilla Thunderbird > Cancel-Lock: sha1:xRoKEw4U0Hmxzz7rG2561/KPAnA= > Content-Language: en-GB > In-Reply-To: <ukdfn5$20ktn$2@dont-email.me> > X-Received-Bytes: 2999
Reply by Martin Brown December 6, 20232023-12-06
On 01/12/2023 20:29, Don Y wrote:
> On 12/1/2023 4:08 AM, Martin Brown wrote:
>> Another simple option would be a write once CD and then you could >> include images for a few different machines on one disk. That way any >> copy of the right CD will do to make a trashed machine work again. > > Machines are now being offered without optical drives.&nbsp; I think the design > rationale is that you can access RUNTIME media via the network connection > and boot media via USB devices. > > This is especially true for smaller machines (which are a favorite of > the clients because they don't want to have to lug something with a > 17" display)
If they have a full size sD slot then I favour Phils suggestion of a micro sD in an sD carrier write protected with a spec of araldite.
> [I have a pair of netbooks, here, that I keep because they *are* > so small.&nbsp; I can slip them BOTH in a desk drawer instead of having > to store them on a shelf in a laptop bag.]
My favourite portable for travelling is an ASUS T1000 (not made of liquid metal) 11" diagonal screen. It's not fast, a bit long in the tooth now but lasts a long time and is very small. It even comes apart so that you can use the screen as a tablet.
> >> Or even the micro CDs that come with drivers on. > > I've been exploring UEFI BIOSes (for another project) with the goal > of making a machine unusable as a generic PC (prevent the OS from > being installed).&nbsp; If this bears fruit, I may be able to take some > information from that and use it to cripple these machines to > protect the HPA and boot record (e.g., block writes to any of > those areas so an OS install throws an error)
That sounds like hard work for little gain. BIOSes can also be overwritten. -- Martin Brown
Reply by a a December 1, 20232023-12-01
The arsehole Don Y <blockedofcourse@foo.invalid> persisting in being an Off-topic troll...

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Don Y <blockedofcourse@foo.invalid> wrote:

> Path: not-for-mail > From: Don Y <blockedofcourse@foo.invalid> > Newsgroups: sci.electronics.design > Subject: Re: cheap usb ("thumb") drives > Date: Fri, 1 Dec 2023 13:29:15 -0700 > Organization: A noiseless patient Spider > Lines: 258 > Message-ID: <ukdfn5$20ktn$2@dont-email.me> > References: <uk8317$v4vl$1@dont-email.me> <slrnumflkc.v1f.dan@djph.net> > <uk9pjr$1b0dt$1@dont-email.me> <uk9udg$1boju$3@dont-email.me> > <ukcer9$1rga1$1@dont-email.me> > MIME-Version: 1.0 > Content-Type: text/plain; charset=UTF-8; format=flowed > Content-Transfer-Encoding: 8bit > Injection-Date: Fri, 1 Dec 2023 20:29:25 -0000 (UTC) > Injection-Info: dont-email.me; posting-host="f576992f39d445d0e694d726f7b75e86"; > logging-data="2118583"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+v3bNSfQU9tFeBN3lrJ4EN" > User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:102.0) Gecko/20100101 > Thunderbird/102.2.2 > Cancel-Lock: sha1:MsZTChoXYcGs9+/8uA8zubKE1eA= > Content-Language: en-US > In-Reply-To: <ukcer9$1rga1$1@dont-email.me> > X-Received-Bytes: 13473
Reply by Don Y December 1, 20232023-12-01
On 12/1/2023 4:08 AM, Martin Brown wrote:
> On 30/11/2023 12:15, Don Y wrote: >> On 11/30/2023 3:53 AM, Martin Brown wrote: >>> On 30/11/2023 00:24, Dan Purgert wrote: >>>> On 2023-11-29, Don Y wrote: >>>>> I've got a box that builds a "backup partition" on a machine >>>>> and then invokes it to install the OS/apps prior to distribution. >>>>> >>>>> Some of the clients are hosing the backup partition by trying to >>>>> upgrade to Windows, etc. >>>> >>>> Not your problem if they trash their box, is it? >>> >>> It might be. >> >> If your (paying) customer trashes the item he BOUGHT from you, >> do you tell him to go suck eggs because he mistreated it? >> How much responsibility can he heap on you for creating a >> product that was so EASILY mistreated? > > Depends on what you mean by easily.
You know, like accepting an offer to upgrade to Windows N+1? (seems like it would qualify as an "easy" thing to do (read: mistake to make) That being the thing that is hosing my restore strategy.
> Few devices with spinning rust in can > survive being dropped 3' onto a concrete floor, iPads and mobile phones are > even more fragile. My old one had a bit missing from its "Indestructible" > gorilla glass but still worked. My wife had someone drop an iPad destroying it > beyond economic repair.
The issue boils down to how much you are willing to accommodate "customers" that, LEGALLY, you are not obligated. If you want to keep a customer, you tend to "eat" things that your lawyers might tell you aren't necessary. If you have lots of competition and can easily *lose* a customer, then you likely "do them a favor" (esp if the favor only consumes the intangible called "time" -- which nonprofits consider to be "free"). Also, if your customer has no other recourse AND your purpose for existing (nonprofit) is to cater to that need, then how do you rationalize screwing them "on a technicality" (cuz that's how THEY will see it -- and they are tuned into "their" community of "other customers") [This, BTW, is why abuses are so common; one guy discovers a way to beat the system and word quickly spreads amongst his "peers". It's also why you can't just implement things as "policy" -- they will learn "Ask Debbie for a replacement, she's a pushover! If you ask Barbara, you're screwed..."]
>> Even if you refuse to comp him for his losses, do you, also, >> refuse to do any further business with him? > > Potentially. We took to putting telltales into the shipping package after one > damaged machine came back with clear evidence that it had stood upside down in > 12" of salty water long enough for mild steel parts to go rusty. That pretty > much clinched who was at fault (it was the sort of kit that is shipped in air > floatation supports "this way up!"). > > Most spectacular one to repair we ever had was when they dropped one from the > cargo bay door of a 747. It was never the same again.
Again, non-profit world vs. "for profit". We had a customer clone our control algorithms (PLC-based) to avoid having to pay US for the PLC, etc. Do we stop doing business with them (when there are only a dozen or so such customers, worldwide)? No. What you do is NOT (significantly) discount the other bits of kit that they have to buy from you so their overall costs (buying the PLC from someone else) remain unchanged; you just shift the margin into other items. AND, you refuse to accept contracts to customize the control software, going forward! I.e., you let THEM support themselves (which is why they argued -- to their management -- that they should take on the controls, internally. Now, they are at a competitive disadvantage cuz you WILL take on customization for other customers -- THEIR COMPETITORS!
>> When your customer doesn't give you monies for your product, >> the dynamics change!&nbsp; ("You've been a bad boy!&nbsp; We're going to >> cut our ties to you...") > > Absolutely. I had a strict policy of no support for existing work until my > bills were paid.
No, that's "when your customer doesn't give you monies THAT YOU ARE OWED". Different from "when customer is not EXPECTED to give you monies".
> Some of the large companies I worked for as an employee and > then later as a contractor would only pay their bigger bills when someone from > the bailiffs turned up to take the fax machine away. I knew their systems and > MO so I made damn sure that I got paid on time and in full.
I had a different approach: I simply wouldn't work for them, ever again. And, as the LOCAL community of people on which they could draw for the services I provided was small, it was easy to make sure other folks knew "I'd been stiffed". So, if THEY opted to work for said client, they would take steps to ensure payment up front. [I eventually settled on 1/3 up front -- which means YOU are at risk for 1/3 the value of the contract, INITIALLY; then 1/3 at the halfway point -- at which point, I had 50% effort invested but only been paid for 33% so 33% of what I should expect to receive is at risk until the second payment is made; then the final 1/3 at signoff. This approach shifts the risk back and forth as well as limiting it's magnitude. (I stopped doing T&M jobs long ago as I want control over the extent of a project)]
>>>> Pretty durable.&nbsp; It's the writes that wear out the flash / cause it to >>>> fail. >>> >>> That or the mechanics. I have seen particularly cack handed people break USB >>> sticks off (more often TV tuners) leaving part of the thing still in the >>> machine. This can be terminal for the USB socket too. >>> >>> If it writes and verifies OK then it should be good for quite a few reads if >>> it is looked after. >> >> "Looked after" is a problem.&nbsp; The beauty of the restore partition was that >> they didn't have to *do* anything to have it available.&nbsp; The thumb drive will >> require them to keep it on hand... somewhere. > > Why not continue to use the partition method and keep this option as a backup. > I suspect the USB stick will get reused though. You could perhaps make all the > important files invisible to naive end users.
The restore partition was invisible except for a boot prompt/keystroke. I hid the image in the HPA so the OS couldn't *normally* muck with it. But, if the boot record got clobbered, then my custom bootstrap would be toasted so there was no way to even invoke the process.
>> OTOH, if they misplace it, then THEY are inconvenienced as they will have >> to bring the machine into the shop.&nbsp; On public transportation.&nbsp; Time that >> they could have used for some other purpose (essential or recreational). >> >> I was hoping the drives could be made non-reusable (R/O) to eliminate >> their being used/traded/sold for purposes other than as THEIR backup: >> >> &nbsp;&nbsp;&nbsp; "I lost my thumb drive; can I have another?" >> >> &nbsp;&nbsp;&nbsp; "OK, I'll put in a work order to have one made for you.&nbsp; What's >> &nbsp;&nbsp;&nbsp; your machine's serial number (so we can look up the correct >> &nbsp;&nbsp;&nbsp; image to place on the drive for YOUR machine)?&nbsp; Oh, you don't have >> &nbsp;&nbsp;&nbsp; that handy?&nbsp; Well, get back to us when you do..." > > I can see it could be complex if the installed based is inhomogenous.
Machines come to us from a variety of sources. Most often, a business upgrading to some newer version of Windows *or* just upgrading hardware (e.g., moving from desktops to diskless workstations). So, any solution has to work with a "generic computer". E.g., I can't count on the BIOS having support for a restore partition via a hotkey. But, disk drives are present in all computers as is the NORMAL boot mechanism. And, the HPA. If this is now a problem, I can still resort to booting from a USB drive (as most BIOSes support this -- though it may be necessary to reconfigure boot settings in that particular bios).
>>> Longevity might be an issue longer term so not in the sun and kept cool and >>> dry would make sense. I have had the odd really cheap and nasty one croak on >>> first use but it is rare. >>> >>> Leave it in a machine shop full of metal swarf and all bets are off! >> >> Many of these kids don't have permanent places to *sleep* (let alone LIVE). >> So, everything that they have to keep track of is a challenge.&nbsp; Our GOAL >> isn't to make their life any harder.&nbsp; OTOH, *they* should assume responsibility >> for maintaining their improved quality of life and not just ASSUME that >> we'll forever be accommodating their LACK of responsibility. >> >> We used to give out SFF desktop machines.&nbsp; But, that was limited to >> kids who had a place to SET UP such a machine! >> >> And, if their living arrangements (inevitably "temporary") changed, >> the machine could get lost (left behind) in the "move". > > I find it hard to work out what to do for the best under these tricky > constraints. I've done some voluntary work for organisations where everything > had to be chained down to the desks to prevent snatch thieves but never > anything quite so complicated.
In addition to having (ahem) "dubious" clients, we also have "tenuous" volunteers. Most volunteers are developmentally disabled, autistic, physically handicapped, etc. (They spend time with us as a form of occupational therapy... give them something to do, something to focus on, etc.) Others may be present solely to satisfy court-ordered probation ("community service") -- so, they might be *able* to do the work but aren't going to bust their ass because they often feel like THEY are the victim and this is unfair punishment ("Really? I don't have to sign your attendance report. You can pick up trash on the side of the highway in 100F weather if you're not happy *here*!") I've walked into the bathroom and found folks shooting up. We've had to have folks escorted off the property for violent outbursts and assaults, etc. And, turnover is relatively high -- someone "doing time" is not likely to keep coming after his "sentence" has been completed. It's just a completely different environment from a 9-to-5 (where folks are concerned about KEEPING their position!)
>> Or, *sold*... even $10 is a win if the machine didn't cost you anything >> AND if you think you can get another, for free! > > I can see why you need to lock things down. > > There are too many videos of how to format a write protected USB drive for you > to stand much chance of preventing it. Use cheap nasty small ones would be the > best idea that I can come up with. Ones that are too small to have any resale > value.
I think if I intercept the *normal* driver install (VID/PID for THIS drive), I can replace it with something that doesn't support write operations at the device level. But, that only locks the drive while it is installed in THIS machine.
> Another simple option would be a write once CD and then you could include > images for a few different machines on one disk. That way any copy of the right > CD will do to make a trashed machine work again.
Machines are now being offered without optical drives. I think the design rationale is that you can access RUNTIME media via the network connection and boot media via USB devices. This is especially true for smaller machines (which are a favorite of the clients because they don't want to have to lug something with a 17" display) [I have a pair of netbooks, here, that I keep because they *are* so small. I can slip them BOTH in a desk drawer instead of having to store them on a shelf in a laptop bag.]
> Or even the micro CDs that come with drivers on.
I've been exploring UEFI BIOSes (for another project) with the goal of making a machine unusable as a generic PC (prevent the OS from being installed). If this bears fruit, I may be able to take some information from that and use it to cripple these machines to protect the HPA and boot record (e.g., block writes to any of those areas so an OS install throws an error)