Posts Tagged Argentina

dd-wrt and 802.11d woes

In Argentina it’s quite difficult to buy a wifi router which is configured correctly for use in this country (with the exception of those that come “free” with your cable etc.).  The majority of network equipment that you find here is bought (over the counter) in other countries, and imported through “unofficial” channels.  This presents a problem with wifi routers, which are often configured for another regulatory domain — as generally those who use them don’t bother (or don’t know how) to fix them.

I live in an highly congested wifi zone (a kismet scan run from my laptop yesterday found an incredible 4200 distinct stations!).  A few hundred of these are access points, most have 802.11d enabled, and many of these transmit a country code that is not AR (i.e. Argentina).  Aside from probably being immoral, that’s not such a big deal.  But …

Enter Mac OS X.

Read the rest of this entry »

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Me versus the Argentine Ants

Since we moved into our new apartment (about 6 months ago) we’ve had incredible problems with insects:

  • First it was mosquitoes.  Literally hundreds of them would be wandering around our bedroom each night (we used to vacuum them!), until we found the (several) places they were coming in.
  • Next it was cockroaches, large and small, to be found in the most unexpected of places.  Roaches are standard fare in this city however, so a few visits from the exterminator to the building put an end to them (at least for the present).
  • And lastly, we’ve had ants.

The Argentine AntTiny Argentine Ants, maybe 2 to 3 millimetres in length, turning up everywhere that there’s food exposed.  We’d find them in the sink every morning if we didn’t do the washing-up the night before.  In cakes (even when in a supposedly airtight container), in the rubbish bin, in the bathroom (very often in the bath for some reason?  I guess they’re easier to see there), and finally, the other day, feasting on our medialunas on the living-room table.

We took to following them (they make these hilarious little trails) and blocking the hole they came through with a little silicone gel.  This stopped them for a short while, but they quickly find another route.

Other common remedies (washing their trails with soapy water, spraying with vinegar, salt barriers, coffee grounds) also offered brief respite.

Happily now however, it appears that we have found a solution (although I say that very tentatively, it’s early days yet) – boric acid.  This wondrous substance (used for cleaning apparently) works as a slow-acting poison which allows the ants to bring the foodstuff (with which it is mixed) back to the nest before killing them (and hence destroying the ants in the nest also).

We tried two different mixtures:

  1. 50% boric acid + 50% sugar, diluted in water (enough to dissolve the sugar).  Soak kitchen paper towels in the solution and place on a small plate (the sugary solution will makes a mess otherwise).
  2. 25% boric acid + 75% honey, mixed until the boric acid dissolves.
Boric Acid + Honey solution

Ants eating the Boric Acid & Honey solution.

Although both mixtures were effective (the ants ate both), the honey mixture (b) was much more popular (so popular in fact, that many of the ants drowned themselves in it).

To give an idea of scale in the picture on the left: the piece of plastic that contains the honey solution is part of a light switch – about the size of a 2 euro coin.

The ants found the mixtures after about 2 hours (which we placed in 4 different locations around the apartment).  For the next 12 hours or so we had a continuous stream of guests (around 30 eating at time), then the numbers started to gradually decrease, down to around 5 after 24 hours.  And now, after about 48 hours there is usually just one or two.

Of course we can’t be sure yet if this will be a permanent solution (there is still a question whether the ants made it back to the nest(s) alive), but it is certainly looking positive for the present.

Argentine ants are quite unique by the way: they share nests, never fight amongst themselves, and have several queens.  Well worth reading about.

Edit (5 days later): Well the ants stopped coming to these particular buffet lunches, however we noticed that they are still very much present elsewhere in the apartment – so it seems that they became aware of the poison and have started avoiding it.

A little googling turned up this (authoritative-sounding) document which states that

For boric acid or borate baits, the concentration of active ingredient that will be most effective in killing the colony (rather than just stopping the ant trail) is between 0.5% and 2%. Higher concentrations may be used to quickly eliminate ants indoors.

So our 25% to 50% concentration was insane overkill!

It also states that,

The optimum sugar concentration in liquid bait is 25%.

So, again, our 50% to 75% sugar content was somewhat overzealous :)

Back to the drawing board then.  We’ve mixed new traps, this time with 1% Boric Acid, 25% sugar, and the remainder water.  We’ve placed these (4 of them) in (new) strategic locations around the apartment.  Interest in them has been very poor so far: they’ve been down for about 12 hours now, and on the few occasions that we’ve checked we’ve had no more than 2 ants at any one trap (often none).

We’ll give it some time though and see how it goes :)

Update (6 weeks later): Well the ants did express an interest in the new traps.  For a week or two the numbers held at about 5 to 10 ants per trap at any one time (and even the corpses building up around the traps didn’t seem to deter then), and gradually the numbers reduced to maybe one at a time.

We were considering removing the traps (now littered with ant corpses), when suddenly the numbers jumped significantly about a week ago, up to 10 or 15 at a time.  These appeared to be new ants, often bigger than the previous ones (if only very slightly), who were re-exploring all the tracks that the other ants had used previously (even the dead-ends).

Now this new batch has begun to reduce in number also, and the ants arriving are getting smaller – so it would appear that the traps are having the desired effect on this nest also (or at least the ants have communicated to one another that the traps should be avoided).

The plan currently is to leave the traps in place for another few weeks – until they no longer receive visitors.

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OS X: Fix Argentina DST October 2009

Date%20&%20TimeWell, at almost the last minute, DST was cancelled in Argentina this year. And this broke things, mostly computers. (Not for the first time either, the same thing happened two years ago here).

The debian folk came out with a fix at the last minute: so that fixed the linux machines, but OS X is a slower beast to move, so it’ll be a while before any change works its way through. In the meantime, Mac users in Argentina are left with broken clocks.

If you just want your clock to show the correct time for Argentina again, and don’t really care about the why, then just download and install the following:
Argentina_DST_Update_2.pkg – for 10.6.x only!
(Updated 2010-03-15)

I am no Mac expert, and this isn’t entirely tested, so be warned.

Anywho, this is how to update the tz data (aka zoneinfo), which should, in theory, fix the problem:

mkdir tzfix
cd tzfix/
curl | tar -zxvf -
vi +219 southamerica

Change the two lines:

Rule Arg 2008 max - Mar Sun>=15 0:00 0 -
Rule Arg 2008 max - Oct Sun>=15 0:00 1:00 S

to the following

Rule Arg 2008 2009 - Mar Sun>=15 0:00 0 -
Rule Arg 2008 only
- Oct Sun>=15 0:00 1:00 S

(i.e. just two words to change). If it makes you feel better, here’s a diff.

Ok, save & close, and then compile it as follows:

sudo zic southamerica
sudo cp /usr/share/zoneinfo/America/Argentina/Buenos_Aires /usr/share/zoneinfo/America/Buenos_Aires

The sudo is necessary because you’re changing /usr/share/zoneinfo.
And that’s mostly it. Verify that it worked as follows:

zdump America/Argentina/Buenos_Aires
America/Argentina/Buenos_Aires Sun Oct 18 20:43:42 2009 ART

(note that the timezone is now ART, not ARST as previously).

So that fixes things for most of the command-line stuff. But you’ll notice that the clock on your desktop, iCal, and others, are still incorrect. We need to fix the ICU database also. Thankfully the latest sources are available for this from apple itself:

curl -O
tar -zxf ICU-400.37.tar.gz
cd ICU-400.37/icuSources

ICU doesn’t come with the tzdata, but the readme in tzcode helpfully notes that if we place the tzdata*.tar.gz file in tools/tzcode/ it will be compiled automatically. You can pack up your own tzdata2009n.tar.gz that we used earlier if you wish, or use the one I prepared here:

cd tools/tzcode/
curl -o
cd ../../
./runConfigureICU MacOSX --with-data-packaging=archive
sudo install -o root -g wheel -m 0644 -Sp data/out/icudt40l.dat /usr/share/icu/icudt40l.dat

And that’s it. We have a new ICU database. Reboot to see the changes.

Update (21st October): This technique works on the iPhone too. The iPhone already has zic (well, at least my one has), so you can simply copy your modified southamerica file onto the phone somewhere, and run (as root):

zic southamerica
cp /usr/share/zoneinfo/America/Argentina/Buenos_Aires /usr/share/zoneinfo/America/Buenos_Aires

And you can simply copy the data/out/icudt40l.dat you created for OS X into /usr/share/icu/icudt40l.dat on the iPhone. It causes Springboard to crash, but after a reboot everything works perfectly.

Update (10th November): I can’t believe it, today 10.6.2 update broke the damn icu stuff again.

mkdir 10_6_2_fix
cd 10_6_2_fix/
curl -O
tar -zxf ICU-400.37.tar.gz
cd ICU-400.37/icuSources/tools/tzcode/
curl -O
cd ../../
sudo install -o root -g wheel -m 0644 -Sp data/out/icudt40l.dat /usr/share/icu/icudt40l.dat

Thanks to Jonathan Tapicer for pointing out that the tzdata file name has been updated (now at version R).

Update (5th February): I’ve had several requests to package this up in an installer, so here goes:
Argentina_DST_Update.pkg – for 10.6.x only!
(I don’t have a 10.5.8 any longer, so I can’t compile for it, sorry)

Update (15th March 2010): Yes, the ICU fix is broken again today. The problem seems to be more to do with automatic timezone detection (which OS X is now seeing as GMT -4) than anything to do with zoneinfo. For now, to fix it:

  • Download and install the new Argentina_DST_Update_2.pkg – for 10.6.x only!
  • Open a terminal and type:
    systemsetup -setusingnetworktime off
    systemsetup -settimezone America/Argentina/Buenos_Aires

This is fairly straightforward: it disables automatic timezone detection, and sets the timezone manually (you can use the -listtimezones switch to see a list of available timezones). If anyone knows how to update DateAndTime.prefPane (which appears to use GeoKit) please let me know.

Update (4th April 2010): I’m pleased to announce that 10.6.3 includes updated tzdata for Argentina (and elsewhere) that fixes all this silliness. Get it now (via software update) to make this problem go away.

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