Older blog entries for elwell (starting at number 85)

15 Jan 2012 (updated 27 Jan 2012 at 11:40 UTC) »

Metering

So I finally got round to wiring in the 'Teleinfo' shield into my EDF meter (see my earlier post for more info) and left it running while we're away. Hacked up an initial couple of graphs using trusty gnuplot: exhibits A and B -

It's rather easy to spot where the fridge-freezer kicks in, but more worrying is the fact that the baseline never dips below 170VA. The only things that should have been running in that time was my via-eden server, with one HDD, the livebox and samknows monitoring box. I suspect I need to investigate more.

Made a minor hack to the shield as digi-6 is used by the LED on a nanode - but digi-7 is free.
Details were tweeted over here. Next up is to get it sending the info out to main box (well, another nanode or my bifferboard) and spitting to pachube and / or a jeelabs display board.

Syndicated 2012-01-15 22:34:00 (Updated 2012-01-27 10:49:08) from Elwell

Happy Birthday

I finally got round to assembling my birthday present. Shiny toys FTW :-)


Syndicated 2012-01-06 12:28:00 (Updated 2012-01-06 12:28:32) from Elwell

The Perils of CDNs

So CERN have just held a popular webcast event to announce the latest results in the search for the Higgs. Many of the webcast viewers (no I don't have usage stats) were complaining that the stream was choppy. What I did notice on my laptop (couldn't get near the auditorium) was that the main libflashplayer traffic was inbound from 93.174.99.0/24 VELOCIX-EU - could this be the CDN used by Groovy Gecko?

Not having an onsite mirror though then meant that each member of staff watching was then pulling data *in* to site as the traffic graph shows:



I'm sure this can't be efficient... Ho Hum.


Syndicated 2011-12-13 15:19:00 (Updated 2011-12-13 15:19:06) from Elwell

Another year of LHC Secrecy

So, another year of LHC running comes to a successful close, Once again we've managed to keep the real facts hidden from everyone - Not the Higgs (as thats's being discussed next week) but more importantlt that the whole of the LHC is actually a spinoff from one of the major Data Centre companies who had outgrown their shed. The Proof? why - of course...

however, best to keep it a secret - its easier to get runding for a mythical 27km tunnel than a shed :-) Oh, and a lot less sexy in the books too...

Syndicated 2011-12-08 14:44:00 (Updated 2011-12-08 14:57:51) from Elwell

25 Nov 2011 (updated 27 Jan 2012 at 11:40 UTC) »

Sniff...


Updated to include the plots from monitoring box:

Syndicated 2011-11-25 13:12:00 (Updated 2012-01-27 10:48:46) from Elwell

24 Nov 2011 (updated 24 Nov 2011 at 14:05 UTC) »

FTTH update

So, I'm still (till I move flat) with k-net at the flat, and have a monitoring whitebox hanging off my router.

So Far, speed has been consistenly high - downloads in the 90Mb/s range. They are only (heh, 'only') seeing uploads of ~30Mb/s, but I know I can get higher than that using a box closer to the reso-lian network or to work.

Sniff, anyway thats only till the end of the month and then I'm back to orange.fr till May. Somehow I don't think I'll be getting this off my ADSL line...

Syndicated 2011-11-24 10:55:00 (Updated 2011-11-24 13:47:25) from Elwell

PoE Network controlled signage

I may have a requirement for several 'remote controlled' illuminated signs. (where remote could be network driven) - These aren't Scrolling LED 'calls in queue' type ones, but more the warning 'Laser on', 'Mic Live', 'Conveyor Running' type ones.

Normally these things seem to be driven directly from some local switchgear or output, but what if you want to gather status centrally , or illuminate the sign depending on some remote sensor (be it a web tsunami alert or the boss' car being picked up on the ANPR at the gate)

Cue a quick hacky prototype: Take one nanode and use the digital outputs to drive a mosfet to switch some cheap LED strips from IKEA. So far so good, but that requires a 12v (since thats what the strips use) supply. The nanode can take that on the screw inputs if you add a heatsink to the reguator, but I'd rather get rid of the PSU alltogether: cue a cheapo 802.3af PoE splitter from TP-Link, and I have the whole lot driveable off one RJ45 cable.

Onwards to software, and it looks like bitlash / restuino look useful (esp if I get the whole lot working with DHCP too).

Anyway, with a range of lighting areas possible (thanks to addressable outputs on the nanode) per display, the option to have a nice facia with multiple 'zones' illuminated is possible. Now to find a nice case...


Syndicated 2011-09-28 21:00:00 (Updated 2011-09-28 21:00:26) from Elwell

puppet /. facter / v12n

As I'm starting to get into puppet, especially when used with the foreman for dashboard display, I've started noticing a few (fixable) oddities

1st up ios that not all RHEL clones are treated equally -- some patches are just adding detection and flaggin, others go the full hog and make sure its in all the "constrain:" sections in facter too. I guess I need to do a code review and pull in the extras. Cue lots of different VMs
(the joys of a weeks home leave from work..)

secondly, virtualisation detection is 'flakey' -- some (vmware) are really well detected, but new kernels give false positives (see issue #7723) so I'm going to set about tidying these up and adding hyper-V detection properly

Syndicated 2011-09-01 08:53:00 (Updated 2011-09-01 08:53:36) from Elwell

FTTH / Reso-LIAIN / K-Net

Executive Summary:


I've had fibre installed to the flat. In this area it's all organised by Reso-LIAin who have 'local' ISPs who resell their network. Luckily for me one of the PoPs is located at work so I have nice small (<2ms) pings to site.


So what's involved? Choose your ISP from the shortlist (of about 5) -- all roughly the same prices, some offering more bundled stuff at cost. I ended up with 'k-net' (formerly known as kwaoo.com). They seem to be rather dependent on one supplier if you look at their AS24904. Contractors from reso-lian show up to pull the fibres into your property -- In my case they'd already run multicore into the building (1st and 3rd floors had breakout boxes installed) and I was the first to get it from there. They pull (through the france telecom duct -- which should be installed anyway) a 2-core fibre and terminate it at the CPE (which must be powered, so you have to define a location within reach of a wall-wart. They will put the CPE up to 5m from the france telecom entry point, in my case I asked for it in the walk in cupboard. Being an old flat, the duct was smaller than current Normes (building standards) and partially blocked. when they repulled the phone cable (in use for ADSL) they managed to snap it. It now leaves the duct at floor level rather than in the patress. Hmm.
cpe

CIMG6643

The 4 ethernet ports are split from 2 vlans - ports one and two carry 'internet' traffic - you give the MAC address of your router (I purchased my own) and they put it in the DHCP server. (you get a static IPv4 address). Ports three and four are for the IPTV service. This is multicast and although they supply a set top box, I've not bothered renting one, as I'll just watch it with VLC instead. Status of the TV streams is available (from reso-liain) at http://81.18.191.108/tv/liste_tv.html (found via their forum).


Phone service is VoIP -- They will port your existing number (this is the only resason my freebox is still active - am waiting till thats done before cancelling service) and will sell or rent you an ATA. Since they send config details in the mail, I shall use my polycom and if brave the SPA3102.

Disadvantages: No IPv6 yet. boo. Especally as I was used to having it with free. Other than that? I've only mailed specific tech Questions at their helpdesk and theyve been OK (such as can you set reverse dns to ...... -- which they do :-)

Syndicated 2011-08-24 23:01:00 from Elwell

Shuttle bus tracker

Not that I tend to err, leave things till last possible minute or anything, but I'd really like to have a tracking system on the CERN shuttle busses, so that I can stay in the office until I know the bus is coming. (or, armed with a mobile device waiting at the stop, see where it is)

So - I was thinking something embedded ish that contained a cheapo GPS chipset (probably good enough signal on the dasboard, a 2 line LCD and a keypad

something UI ish for driver along the lines of 'select route:'
and then it'd show the route, upcoming timetabled stops

backhaul to site would be GSM (should be able to transmit a small UDP packet of transponder#,Route#,Position,timestamp) to a central server.

The folks over at rpi.edu (yes, they started concerto too) already have some code that looks interesting at https://github.com/wtg/shuttle_tracking/


Question is, would it be cost effective to roll our own, and if not, who's offering the best / cheapest (open) system out there?

Syndicated 2011-08-03 07:54:00 (Updated 2011-08-03 07:54:06) from Elwell

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