At LCA2012, I spent some time learning about the poster child of the Open Hardware world, Arduino. I bought the Pebble v2 demo kit and attended the “Arduino miniconf”, and the “bag schwag” included the Freetronics LeoStick. Here’s a demo video I made of a Raining display on the LCD: https://youtube.com/watch?v=C8twFFL32Zs It uses the Pebble v2’s 20x4 LCD display and custom characters to display a “rain” effect (the LCD needs to be mounted sideways, as shown in the video).
Today is the day for my IPv6/Automatic reverse DNS mappings presentation at LCA2012. Get the custom pymds fork here; it’ll be merged upstream shortly-ish.
This is semi-draft, as I haven’t gotten around to testing the packages I build… Caught out needing new “Sun” Java packages for Ubuntu, by the DLJ revocation? Grab a usable set of build source packages from http://archive.canonical.com/ubuntu/pool/partner/s/sun-java6/ - you’ll need an *.orig.tar.gz, a *.dsc, and a *.debian.tar.gz file for the version you’ve picked. I used a 6.26 version from Natty. Grab a latest (currently 6u30) “bin” Linux packages for each architecture from http://www.
Just got this email…: We're pleased to announce that your proposal(s) has/have been ACCEPTED for LCA2012. <SNIP> --- IPv6 Dynamic Reverse Mapping - the magic, misery and mayhem --- So - wow! I’ll see you there :)
DNS is a wonderful distributed system, with plenty of safeguards and fallbacks to ensure continuous operation. But still, screwups happen. Here’s some tips on what to do to try to ensure you aren’t caught out in the cold. Tip 1: Have multiple servers. Without a doubt, this is the biggest tip about DNS. Designed in from the beginning was an assumption that you’d have multiple nameservers for a given zone. So… have them!
If you’re serious about your call data records - because you’re billing customers, or because you want to automatically reconcile calls against your invoice - then they’d better be accurate. An easy win here is to normalise the numbers you call. In South Australia, a number listed as “(08) 5550 1234” can be dialled as either 0855501234 or 55501234 - the “08” prefix is optional, since it merely clarifies the area code.
CallerID information is carried along quite readily within the SIP protocol; most SIP providers pass that along to their customers for free. Other than just showing it as “This is the number the call is coming from”, can we do something more useful? Absolutely! As an example, imagine the contexts incoming (where calls go to when they come in to Asterisk from a SIP provider) and outgoing (which allows outbound calls from internal phones).
I did a presentation to the SA chapter of SAGE-AU last night - the first presentation I’ve given in a very long time! Download the slides here Overall, I think it went pretty well - it didn’t seem too obvious that I hadn’t had a chance to practice the talking that went with the presentation, and only one of my demonstrations failed. A handy hint for doing PDF exports from OpenOffice.
We interrupt your regularly scheduled broadcast of quality sysadmin programming to bring you a brief announcement on using SSH and hacky port forwards to access something via a LAN IP over the Internet. If I have a server at home that can only be accessed via 192.168.1.12 (say) - perhaps because it is a web application that rewrites all internal URLs to always go to that IP - how do I get access?
Please note that this is all personal opinion, and is not a reflection on the opinion, or policies, of any employer, past, present, future, or comma-less. What is IPv6? IPv6 is the next step after our current IPv4 addressing scheme - and not a lot more. Instead of the we-thought-it’d-be-ample 2^32ish addresses, we get the it’ll-be-enough-this-time-for-sure 2^128ish addresses. If nothing else, it’ll take us a long time to run out again!