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

[Rick Moen]

On Tue, Dec 30, 2014 at 1:14 PM, jim <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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