LEAF battery replacement update

New LEAF battery

Just a quick note here – the LEAF battery did finally go under warranty on Sept 24, 2017, and I got it replaced with minimal hassle back in great shape on October 3.  The LeafSPY stats on the new battery actually dropped fairly quickly after I got it which was worrisome, but now (in the very cold weather) it’s holding steady at about 97% state of health, with 62.3Ahr and 90.35Hx.

The stats when it finally dropped the 9th bar were:

Miles: 40623
Ahr: 43.51
Hx: 45.25

I’ve definitely needed that fresh capacity for this harsh winter, it’s been fine, but frigid mornings still show the Guess-o-Meter at as low as 50-60 miles at times.

Return of the low-power server: a 10W, 6.5 terabyte, commodity x86 Linux box

5 years ago, I wrote about the build of the server hosting sandeen.net, which ran using only 18W of power.  After 5 years, it was time for an upgrade, and I’m pleased to say that I put together a much more capable system which now runs at only 10W!  This system handles external email and webserving, as well as handling media serving, energy datalogging, and backup storage for household purposes.  It’s the server which dished up this blog for you today.

sandeen.net wattage, as measured by a Kill-a-Watt meter [amzn]

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No, XFS won’t steal your money

So, the Inquirer runs a story by Chris Merriman today, titled “GreenDispenser malware threatens to take all your dosh from Linux ATMs” which includes this breathless little gem:

GreenDispenser targets the XFS file system, a popular standard for ATMs, originally designed for IRIX but now widely used in Linux. ATMs that use Windows XP Embedded, which is still supported, are not thought to be at risk.

Of course, I found this interesting, and a bit odd.  Could the XFS filesystem possibly be at fault here?  And is the “large and lots” filesystem really used in ATMS?  Let’s see what Proofpoint, the security firm who discovered it has to say about the subject:

Specifically, GreenDispenser like its predecessors interacts with the XFS middleware [4], which is widely adopted by various ATM vendors.

That handy link & footnote leads us to Wikipedia, which explains that “XFS middleware” refers to CEN/XFS, which is not in any way related to the XFS filesystem, or Linux, and is in fact Microsoft specific:

CEN/XFS or XFS (eXtensions for Financial Services) provides a client-server architecture for financial applications on the Microsoft Windows platform.

Nice job, Inquirer!  Nice job, Chris Merriman!

(As Jeff points out in the comments, The Inquirer has updated the article as of Sep 25, removing references to LInux and the XFS filesystem.)

Neptune RF water meter frequency hopping pattern

A couple of years ago, my water utility installed new remote-read water meters, Neptune e-Coder R900i, in every home in their service area.  As any casual reader of this blog knows, I’m a big fan of measuring and data when it comes to household resource consumption. I’ve got electricity pretty well covered, but water and gas are still lacking. I could install secondary meters with pulse counters, by that seems silly – I already have remote-read meters installed, it’s just that the data they send isn’t accessible to me. Let’s see if we can start to remedy that! Continue reading

Sage’s challenge to the open storage community – support the Ada Iniative!

The Ada Initiative supports women in open technology and culture – looking around my place of work and various conference halls I’ve visited, I think there’s little doubt that we’ve still got an old boy network running here, and I’d like to see that change.  I have daughters who may or may not get deep into tech culture, and I’m glad there are people like Val working to make it a better place for them if they do.

And she’s recently gotten a nice bit of potential help: Sage Weil of Ceph & Dreamhost fame has issued a challenge: Raise $8192 in 8 days, and he’ll match it.  They’re already on their way.  If you can help, please do.  Power-of-two donations encouraged, but not required.  :) Click the counter below to see their donation page.  Thanks!

Edit: The campaign is over, and donation links have been removed.

How is the Taco SmartPlus recirc pump working in my house?

The Taco SmartPlus hot water recirculation pump is designed to push domestic hot water around a recirculation loop, so that hot water is at the taps when you want it, saving time as well as water down the drain while you wait.  It’s designed to learn your schedule, to avoid energy losses associated with pumps that run 24 hours a day, due to both the electrical energy used, and the lost heat in the loop when there is no hot water demand.

The SmartPlus pump is supposed to be “smart” in the sense that it uses a temperature sensor on the output of your water heater to learn when you use hot water, and adjust its run schedule accordingly.

So I had to find out, “is our smart pump learning?”  And so far, I have to say it’s not. (edit: I think power loss to the pump is the reason, read on) (edit 2: even solving that problem, I’m not happy with the results.  I’ve put it on manual mode and attached a timer.  I gave up on its claimed ability to learn our schedule.) Continue reading

Could wifi thermostats coordinate zone firings?

nest_smallerAs we approach the end of the renovation project on our house, we now find ourselves with three heating zones, vs. the two we had before.  (The 3rd zone is kind of ridiculous; that’s a different story.)

Having 3 zones pretty well dashes my hopes of outfitting the house with Nest thermostats; yes, we could have the main zone on a Nest, and the others not, but that offends my sense of order.  And three thermostats for $750?  Sorry, no.

But this got me thinking.  Wouldn’t it be cool if thermostats on multiple zones could communicate in order to coordinate boiler/furnace firings, to reduce short-cycling and firing losses?  If the zones have a swing of, say, two degrees, one could opportunistically turn on even  if it’s within one degree of its setpoint if another zone is firing, thereby maximizing the current boiler firing cycle.

Or conversely, if one zone has low mass fin tube radiators, and another zone has high mass cast iron, perhaps it would make more sense to try to fire those zones separately, and coordinate that with thermostat communication as well.

I had thought about trying to flesh these ideas out into a patent, but realized I don’t have the money or the lawyers to do so.  There’s probably already a patent out there, anyway.  But if not, here’s prior art & public disclosure.  :)

Nest finally has developed an API, as the Radio Thermostat (RTCA) folks did long ago [pdf].  But I’m not sure those are flexible enough to do this kind of coordination very well; it’d work better if it were in the firmware, I think.

Hey Nest?  If you like this idea, and you implement it, feel free to send me a thermostat.  Or three.  :)