It's a gift (not a newsletter) ; and an offer from SF-LUG

[jim]

     Many thanks! I learn a lot from reading your writing.

     Maybe not "implausible", rather "unlikely"?

     As to sitting in the cold garage rather than sitting in
more comfortable places doing more necessary or
more fun things, if it'll help, I'm willing to come down
bundled in warm socks, sweaters..., to keep you
company, hold screwdrivers, even biblically just sit
and wait (silently).
     God I wish I'd known of the De Anza College
Electronics Swap. I've gotten some great, useful
stuff from such.
     My basic approach to power conditioning is to make
sure powerful spikes don't get through:


power_line-----Coil_A------------Coil_B----------------------Coil_C-----------------------------------o
                     |                | |               
|                        |                 |
                 Cap_A        Cap_B             MOV_A Cap_C        
Surge_Diode   Cap_D
                     |                | |               
|                        |                 |
neutral 
line-------------------------------------------------------------------------------------------------o 



closest to PG&E power, little and fast, closest to internal systems, 
slower but take lots of Joules
double and triple components, give coils lots of iron

anything we can do, we're willing.

jim
415 823 4590 my cellphone, call anytime


On 12/30/2014 01:56 PM, Rick Moen wrote:
>
> On Tue, Dec 30, 2014 at 1:14 PM, jim <jim at well.com 
> <mailto:jim at well.com>> wrote:
>
>     A couple of meetings ago, a few SF-LUG folks agreed to
>     purchase some old box in good working order and with
>     sufficient resources to host a MailMan system. Rick, if
>     this offer will help you, please let us know: we're willing
>     to find, vet, purchase, and deliver. I'm interested in
>     seeing if I can provide an electrical processing system
>     that can protect your machines from over- and under-
>     voltage mishaps.
>
>
> Hey, thanks to all of you for the lovely and thoughtful offer.
>
> Thing is, I actually do have a bunch of hardware sitting in my 
> garage.  At least one of them is very likely a functional 1U or 2U 
> rackmount server, which is the right sort of thing to use.  (Many 
> desktop boxes have things about them that make them unsuitable, such 
> as many desktop machines' ATX power supplies not being able to be 
> configured to bring the machine back up without manual intervention 
> when the power returns after a power outage.)
>
> Just before I went on my last vacation, I moved the hard drives from 
> my server from the failed VA Linux Systems model 2230 to a spare model 
> 2230.  To my relief, I got video and was able to boot an Aptosid live 
> CD.  Even better, I was able to mount my server system's partitions, 
> verified that they were readable, and update my backups of 
> everything.  Thus, at that point, I was no longer in danger of having 
> to revert to an old backup.
>
> Using the live CD, I then attempted to fix the software problems that 
> were the _other_ issue aside from failed hardware.  (To recap, I had 
> been doing system updates, and (skipping some details) the system 
> segfaulted in the middle of the system software upgrade. I cold 
> booted, but there was from that point forward no video at all, nor 
> beeps, i.e., it acted as if I'd had failure of the motherboard or 
> other key system hardware.)   I was not able to find a way to make the 
> system bootable through some hours of experimentation - was getting 
> some bizarre GRUB errors - and had to defer the matter because I had 
> to leave to catch our flight to Barbados.  So, I powered down the machine.
>
> When I got back from Barbados, I found something perplexing:  I heard 
> the system fan running, and saw the blue power light on the front 
> panel, i.e., it was powered up (even though I'd left the system 
> powered down). However, despite that, there was no video.  Cold 
> booting the system resulted in... no video.  This was really bizarre.  
> The symptom suggested that there had been a power outage during my 
> time in the Caribbean, and upon the return of power, my system had 
> come online (I hadn't unplugged it, just powered it down), and that 
> there had then been a second and similar hardware failure.  But this 
> seemed like an implausible coincidence, as perhaps you would agree.
>
> Time and experimentation and use of careful logic can get to the 
> bottom of the matter.  I just haven't lately had the patience to do 
> that, and have been quite busy with other commitments in the 
> meantime.  Sooner or later, I _do_ plan on sitting out in my very cold 
> garage for as long as it takes.  I certainly could give up on 
> debugging the VA Linux Systems gear, and just attempt to build from 
> scratch a replacement software configuration on one of the other spare 
> machines I have.  I'd prefer not to do that, because building a new 
> server configuration instead of just tracking down the one software 
> problem that made my system unbootable is a LARGE amount of extra work.
>
> And, thus, you'll notice, the resource I'm short on is not machines, 
> but rather time, patience, and focus on the problem.
>
> About over/under-voltage:  Last year, concerned about that very thing, 
> I set about dealing with that.  First thing I did was to buy an APC 
> UPS unit over at Central Computer.  However, this never seemed like 
> really the right solution, just the commercially easy thing to 
> acquire:  A UPS isn't actually very great at dealing with power 
> fluctuations (and sometime is useless at that, depending on the type), 
> and also interposes a new single point of failure in the form of a big 
> lead-acid battery that can, itself, bring down your system.  Also, the 
> UPS generates quite a bit of heat, which bloats your PG&E bill, and 
> you have to buy replacement lead-acid battery packs every few years, 
> which are a large percentage of the cost of the entire UPS, each time 
> you have to buy them.
>
> What the UPS mostly does - the problem that it exists to solve - is 
> bridge you across short-duration outages, making it so you don't lose 
> power and have continuous uptime.  Continuous uptime is abstractly 
> nice, but is the thing I care least about:  Linux servers come right 
> back up after power returns.  That's what we have journaled 
> filesystems for.  So, given that fact, why would I want to put a 
> continually expensive, heat-producing, potentially problematic bit of 
> hardware between the AC outlet and my unit, one that isn't even very 
> good at line regulation, and that can be a Single Point of Failure 
> that otherwise wouldn't exist?
>
> In short, I have not been in a hurry to deploy the UPS, because it's 
> mostly a solution to the wrong problem, a solution to a problem I 
> don't care about very much.  On reflection, I realised that the right 
> solution is a line conditioner unit, not a UPS.  And I don't mean the 
> miserable rubbish you can get at Fry's, either.  The problem was: 
>  Where do you get a line conditioner of the variety that people 
> acquire who are serious about the problem?
>
> Last summer, I solved that problem:  I went to the De Anza College 
> Electronics Swap, very early in the morning, and found a vendor who 
> was selling a ham-radio-grade line conditioner unit.  I have that with 
> my gear, and expect to use it going forward.
>
> Thanks again.

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