[Tfug] Small-ish (capacity + size) disk alternatives

[Tyler Kilian]

There is no IT installation that will be 100% unattended.  If your requirement be that it be based on PC architecture and use PC components, then expect PC problems. 


There are tons of general automation systems that are firmware based and if I were a company looking to build a home controller, I would leverage something along those lines or spec out the system design from scratch.  Either way, the instant I want to store video locally or do anything requiring gigs of data locally, I move from the firmware systems to requiring hard disks. Disks mean disk failures. That's just how it is.

 If I were a company wanting to make it user friendly, I would design an enclosure where the disks are easily pulled (like an Xbox) and mirror them, building in the logic to do this all automatically with simple notifications.  I would make it as small as possible, but ultimately, a system this complex would require a commitment of the user of supplying sufficient space.  It wouldn't be a cheap solution even if it were amazing.  It would take several generations to refine.  All of this, properly done to meet your goals would be doable, but it would be custom.

Instead, your approach is start with a Micro PC and grouse that hard drives aren't reliable enough.  Champagne wishes on the proverbial soda pop budget.

If you really wish to build something like this, you are going to have to accept some limitations and/or be prepared for custom engineering.  Your desires are simply beyond the scope of homebrew tinkering.



On Jan 31, 2013, at 11:50 PM, Bexley Hall <bexley401 at yahoo.com> wrote:

> Hi Tyler,
> 
> On 1/31/2013 10:32 PM, Tyler Kilian wrote:
>> Honestly, I'm not trying to be confrontational, but this thread
>> has thousands of words trying to explain why no manufacturer of
>> hard drives on this planet makes a product sufficient for a home
>> automation project.  I find that hard to believe.
> 
> No one has concluded that "no manufacturer of hard drives on this
> planet" makes an appropriate hard drive (or *other* storage medium
> with high availability and low total system cost per byte).
> 
> And, "a home automation project" grossly simplifies the problem
> domain.  Find me an existing product (money being no object) that
> controls *everything* in your house (note that I said "controls"
> and not "allows YOU to control"... big difference in those few
> words!), surveillance, tracking, multimedia, etc. and *doesn't*
> require you to hire a staff to ensure its continued availability.
> 
> *If* you can find such a beast, then I'd love to know how "widely
> deployed" it is (i.e., how many folks are willing to pay whatever
> it costs to actually install one!).
> 
> In your leisure, you might want to browse the web for "automation"
> and "multimedia" offerings.  You'll find *some* things offered that
> will "run on a PC" (i.e., leaving the reliability issue up to the
> customer).  You'll find lots of things that perform *one* task
> (surveillance, HVAC, music, etc.).  You'll find sensors and actuators
> for a variety of "field" devices (doors, lights, thermostats, etc.).
> You'll find some specialty products that serve very rigidly defined
> needs (e.g., share your FAX with your answering machine; mute your
> TV when your phone rings -- though you'd need to buy one for EACH
> TV...).
> 
> Some will offer limited connectivity options (e.g., forward your
> voice mail as an attachment to an email).  Some will offer fancy
> control/status interfaces (e.g., control panels, graphic displays,
> speech I/O, PC interfaces, etc.).
> 
> About the only thing that these devices will *share* is the AC
> power!  They'll all be isolated little "islands of automation".
> Like having a remote for your TV, another for your DVD, etc.
> Nothing willing (or capable!) to talk with anything else!
> 
> And, with the possible exception of a "setback thermostat", none
> of them will do much to identify *your* needs and usage patterns.
> In short, they'll just be glorified control panels where all the
> intelligence resides in the user's mind.  As such, they don't
> *need* much in terms of computational resources!  (look at how
> little is in your handheld TV remote *control*!!)
> 
>> Even critical IT systems don't have the availability requirements
>> being thrown out here to where folks scrutinize the minutia of drive
>> usage patterns.  Drives fail, they always have, they always will.
> 
> How many UNATTENDED "critical IT systems" do you know of?  Do you
> want to have to take out a service contract to ensure you've got
> a "home automation specialist" on call 24/7 for those times when
> something goes wrong with your home automation system?  "Critical
> IT systems" solve the availability problem by purchasing human
> resources that they can deploy via pagers.  And, paying them
> salaries (or per diem) to *be* available.
> 
> Data centers have special power conditioning, cooling, shielding,
> etc.  And, appropriately sized budgets for those things.  Should
> we plan on a "server room" in all homes built in the future?  And
> solar panels to offset the additional power required for a "data
> center" style solution?
> 
>> I really think a solution exists.
> 
> I'm waiting for someone to point me at it!  :>  I should receive some
> "suggested" drives in tomorrow's mail -- but I can't yet comment on
> how appropriate they are likely to be!
> 
>> The worry, to me, seems unfounded.  If it were me, I'd invest in a
>> good quality drive.
> 
> *Which* drive?  What sort of endurance do you expect from it?
> What's the price point?  What is the total system cost (average
> per year) when you factor in replacements (parts, labor and
> opportunity costs)?  Will your *mother* be able to buy one
> and install it when the existing drive dies??
> 
>> I know that's more than two cents. :)
> 
> The problem is that "commodity parts" are geared to two very different
> markets:  consumers (ever vigilant for low price and EXPECT to discard
> or replace items "frequently" to keep up with technology, The Joneses,
> etc.) and enterprise (who have deep pockets and are willing to throw
> money, equipment and personnel at problems).
> 
> Home automation (BEYOND A GLORIFIED REMOTE CONTROL) wants the
> enterprise's availability levels at the consumer's price point!
> 
> When the Reading Machine was released in the 70's, it's price point
> was *way* too high for an individual to purchase (though Stevie
> Wonder purchased one... "deep pockets").  They were all delivered
> to "organizations/institutions" where they could be shared among
> the clientele served by said organization.
> 
> A big reason for the high cost (besides the low quantity) was
> the cost of support and the timeliness required in that support!
> I.e., if a machine was misbehaving, someone had to be *there*
> the next calendar day (weekends, holidays, etc. notwithstanding).
> It wasn't possible to ship the machine back for repairs nor ship
> out a replacement (think:  washing machine).  And, even if you
> had "skilled staff" on the premises, the components used in the
> machine were not available "off the shelf":
> 
>     "Excuse me... can you tell me which aisle I can find
>     the speech synthesizers in?"
> 
> Last I heard, the newest generation of Reading Machine is
> essentially a glorified cell phone -- affordable for an
> individual (with a fair amount of disposable income).  But,
> more importantly, a replacement can be "overnighted" for
> a modest fee making support (and total effective product cost)
> more affordable
> 
> I've seen this approach (and evolution) followed many times
> with high availability products:  buy a "spare" $30,000 controller
> in case the one you have in production goes down (and you can't
> afford to wait even a *shift* for a replacement -- let alone
> a whole day of travel time!).  Then, when the technology evolves
> to the point where the entire controller will fit in a "flat
> rate USPS box", keep a spare on hand and exchange the suspect
> unit for a replacement, "overnight".
> 
> How many homeowners would engage in *either* sort of approach?
> 
> [We have put off installing an on-demand *or* solar hot water
> system solely because of the support issue.  I've got to pay
> a PLUMBER to service an ELECTRONIC control system??  You can
> already guess what *that* is going to be like!]
> 
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