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Updated: 19 min 22 sec ago

Ben Martin: Terry: Updated Top Shelf

Sun 23rd Nov 2014 19:11
The Kinect is now connected much closer to the tilt axis, giving a much better torque to hold ratio from the servo gearbox. I used some self tapping screws to attach the channel to the bottom of the Kinect. Probably not the cleanest solution but it appears to mount solidly and then you get to bolt that channel to the rest of the assembly. For a closer look the Logitech 1080 webcam is mounted offset from the Kinect. This should give an enjoyable time using the 1080 RGB data and combining the VGA depth mask from the Kinect into a point cloud.





The camera pan/tilt is now at the front of the top shelf and a robot arm is mounted at the back of the shelf. The temptation is high to move the arm onto a platform that is mounted using threaded rod to the back of Terry. All sorts of fun and games to be had with automated "pick up" and move tasks! Also handy for some folks who no longer enjoy having to pick items up from the ground. The camera pan/tilt can rotate around to see first hand what the arm is doing, so to speak.





The wheel assembly is one area that I'm fairly happy with. The yumo rotary encoder runs 1024 P/R and it is attached using an 8:1 down ratio to give an effective "ideal world" 13 bit precision. Yes, there are HAL effect ICs that give better precision, though they don't look as cool ;) The shaft of the motor is the axle for the wheel. It is handy that the shaft is not right in the centre of the motor because you can rotate the motor to move the wheel through an arc, and thus adjust the large alloy gear until it nicely mates with the brass gear on the rotary encoder.







Lower down near the wheels is a second distance sensor which is good for up to around 80cm distance. The scan rate is much slower than the Kinect however.





Things are getting very interesting now. A BeagleBone Black, many Atmel 328s on board, and an Intel j1900 motherboard to run the SLAM software.



Categories: thinktime

Peter Hardy: Making laser-cut backlit control panels

Sun 23rd Nov 2014 15:11

Most of my current arduino projects have had pretty ad-hoc enclosures. You can go a long way with a Jiffy box and a Dremel. Then I bought an embossing label maker to add some text to my boxes (and, OK, everything else — when you have an embossing label maker everything starts to look like an unlabeled thing). My most recent work though has been a pure human interface device. There’s a lot of buttons and switches and displays, and one of my goals for it was to create an enclosure that looked absolutely stunning.

I’ve eventually settled on building backlit panels from laser-etched acrylic, based on a technique I picked up from the MyCockpit forum for simpit builders. Flight sim geek communities are a great resource for learning how to build nice control panels, who knew? I’ve been refining my process to get decent results with a single pass through the laser cutter in my local maker space.

Materials
  • Acrylic sheet. I use 3mm opal translucent sheet. A square metre cost me $80, and now I have more acrylic than I’ll ever need. At current estimates, including all the failed panels I’ve cut, a half metre is still very generous.
  • Spray paint. I’m using a matt grey primer that claimed to be suitable for plastics. It’s been working well so far.

It’ll also need very fine grit sandpaper and masking tape.

Prepare the acrylic

Freshly painted panels, ready to cut.

I cut my sheets in to 250mm square sections. For each section, remove the backing paper from one side and spend a minute or so sanding the face very fine wet and dry paper to give the paint a surface to adhere to. Then apply three coats of paint. At the end you’ll have finished panels ready to cut. And, if you’re like me, some freshly painted furniture to boot.

Design your panel

This part was pretty incredibly frustrating for me. I started out working with LibreCAD, a reasonably full-featured 2D CAD drawing program. That made drawing precise outlines and holes for cutting a breeze, but it’s not particularly good at working with text. I wanted real truetype fonts on my panels, and getting LibreCAD to import font faces in a form it can work with ended up beyond me.

My current workflow is to draw text that I want added in Inkscape. Then convert the text to paths, and export it as a DXF file. That file can then be imported to LibreCAD as a block and placed in my etching layer. The software driving my laser cutter doesn’t like the DXF generated by LibreCAD though, so there’s another step importing the final file in to Inkscape to collapse layers, remove dimensions and save a file that can be downloaded to the laser.

That… mostly works. Sometimes the text paths LibreCAD saves just don’t generate easily filled objects and the laser gets confused and it all goes pearshaped. Right now I’m still loading the text blocks in to LibreCAD but only using them as a visual guide. When doing final prep for cutting I still replace the text on the panel in Inkscape, to ensure a happy etching experience.

Cut the panel

Tuning etching settings for good clear lettering

I did a dummy cut with holes and a combination of angular and round lettering in all of the sizes I needed. I was using a couple of different sized fonts, and it took me a little while tweaking settings to get a result that looked sharp across the board.

When cutting panels, I order the job so that all of the engraving is first, and the cut for the outline is last. Even though the cutting bed is stationary, warps in the perspex can lead to the panel shifting slightly after the outline is cut.

I learned the hard way that getting excited and removing the paper from the back of the perspex at this point is not a great idea.

Final painting

The panel is finished, but now has raw edges that look ugly and leak light when it’s backlit. Apply masking tape to the front side, along the edges (leaving it overhang but not stuck to the side of the panel), and covering holes. Then place it face down and apply another couple of coats of paint along the edges.

I’m still working on getting this part right. Previous attempts without the masking tape led to paint bleeding under the edge, leading to visible paint drops or the newspaper I had under the panel sticking to the face. Initial tests with the tape look pretty good though.

Once the paint has dried, the backing paper for the panel can be removed and components mounted.

My most recent finished panel.

Next steps

I’m still working on the best way to backlight these panels. Simply lighting up the inside of the enclosure looks good, but seems a bit bland to my mind. I want to start experimenting with with individually lit panels, possibly by countersinking LEDs in to the back of the panel. Mostly because I’m keen on flickering panels, and changing panel backlight colour. But pretty pleased with the overall look so far.

 

Categories: thinktime

Matt Palmer: You stay classy, Uber

Sun 23rd Nov 2014 11:11

You may have heard that Uber has been under a bit of fire lately for its desires to hire private investigators to dig up “dirt” on journalists who are critical of Uber. From using users’ ride data for party entertainment, putting the assistance dogs of blind passengers in the trunk, adding a surcharge to reduce the number of dodgy drivers, or even booking rides with competitors and then cancelling, or using the ride to try and convince the driver to change teams, it’s pretty clear that Uber is a pretty good example of how companies are inherently sociopathic.

However, most of those examples are internal stupidities that happened to be made public. It’s a very rare company that doesn’t do all sorts of shady things, on the assumption that the world will never find out about them. Uber goes quite a bit further, though, and is so out-of-touch with the world that it blogs about analysing people’s sexual activity for amusement.

You’ll note that if you follow the above link, it sends you to the Wayback Machine, and not Uber’s own site. That’s because the original page has recently turned into a 404. Why? Probably because someone at Uber realised that bragging about how Uber employees can amuse themselves by perving on your one night stands might not be a great idea. That still leaves the question open of what sort of a corporate culture makes anyone ever think that inspecting user data for amusement would be a good thing, let alone publicising it? It’s horrific.

Thankfully, despite Uber’s fairly transparent attempt at whitewashing (“clearwashing”?), the good ol’ Wayback Machine helps us to remember what really went on. It would be amusing if Uber tried to pressure the Internet Archive to remove their copies of this blog post (don’t bother, Uber; I’ve got a “Save As” button and I’m not afraid to use it).

In any event, I’ve never used Uber (not that I’ve got one-night stands to analyse, anyway), and I’ll certainly not be patronising them in the future. If you’re not keen on companies amusing themselves with your private data, I suggest you might consider doing the same.

Categories: thinktime

Andrew Pollock: [life] Day 296: The day of walking errands

Sat 22nd Nov 2014 21:11

We did a rather huge amount of pedestrian travel today.

I had the car booked in for a service, so after Sarah dropped Zoe off, and she'd watched a bit of TV, we drove over to Newstead to drop the car off.

I'd packed Zoe's scooter in the boot, and once we left the car dealership, we headed over to the Teneriffe cross-river ferry, which is currently conveniently depositing passengers at Hawthorne. Even more conveniently, the ferry was waiting for us as we arrived.

I'd booked haircuts for us at 10am, and we comfortably made it to the hairdresser with about 10 minutes to spare.

After that, it was time to head over to Tumble Tastics, which was quite close to the hairdresser's. We ended up getting there about 20 minutes early, but that was fine.

After Tumble Tastics, we headed home for lunch, and the car was ready to be picked up, so after a brief rest, we headed out again.

This time, Zoe said she wanted to walk, rather than ride the scooter, so we headed out on foot, reversing our trip.

We were in no particular hurry, so we stopped for a little play in a park over at Newstead that we'd discovered in the morning, and then picked up the car. It was a very hot day, so it was nice to get out of the heat.

On the way home, I discovered that the Hawthorne Markets were on. I had some paperwork to drop off to Zoe's school, so after I filled that out, we walked over to her school, dropped it off, and then walked back to the Hawthorne Markets.

I bumped into one of my fellow Thermomix Consultants, Katia, and got introduced to one of her friends, who it turns out, was at the very first trial Tumble Tastics class we went to. She also had a daughter named Zoe. So my Zoe knocked around with this Zoe and Katia's kids, and we grabbed some dinner there. It was a nice night out.

I love the feeling of community that I have now. I don't think I've had this feeling of being so well established in a place, within such a walking distance, ever before. I am truly grateful for living in such a wonderful neighbourhood and community.

Categories: thinktime

Lev Lafayette: A GnuCash Tutorial

Sat 22nd Nov 2014 17:11

Tutorial presentation of GnuCash given to the CPA Young Professionals group at Victoria University, 19th November, 2014

Categories: thinktime

Craige McWhirter: Craige McWhirter: An Unexpected Journey

Fri 21st Nov 2014 22:11

Earlier this year I was braced for a hard and personally gruelling year. What I didn't expect however, was that after my return to Sydney that an old friend would reveal how she truly felt about me. It was a brave moment for her but fortunately for us both I'd harboured the same feelings toward her.

How was I to know,

That you would rise,

Like a burning angel in my eyes

As expected, this year has certainly lived up to and exceeded those difficult expectations to be undoubtedly the most challenging year of my life. However I've been fortunate to balance that by now having the most amazing woman by my side.

Fiona's love, support, advice and humour has been an unprecedented experience in my life. I've found a lover and a partner in crime with whom I've formed an indomitable team as we've had each others backs through some rather unbelievable trials.

Which brings me to Paris. We walked to Pont de Arts, the bridge across the Seine and added our padlock at the centre of the bridge, amongst the thousands of others and made a wish.

Then we kissed.

I asked Fiona what she wished for but was politely told it was a secret.

I said I would tell her what I wished for, then dropped to one knee and paused for long enough to read the unmistakeable expression of "What are you doing? Get up you idiot!" written across Fiona's face before I produced an engagement ring and asked Fiona to marry me.

Fiona said "yes!".

Before too long,

We'll be together and no one will tear us apart

Before too long,

The words will be spoken I know all the action by heart

Earlier in the night I'd slipped an engagement pendant into Fiona's pocket which she discovered and put around my neck before we celebrated with a meal opposite Notre Dame cathedral.

I still shake my head in disbelief at how two such independent people have found themselves in a place where they cannot imagine their life without the other. Yet that's where we are.

Our life going forward is going to complicated and challenging, however there will be an awful lot of love and we'll have each other's backs all the way.

Thank you Fiona, for bringing such love and light into my life.

I've found the one I've waited for

All this time I've loved you

And never known your face

All this time I've missed you

And searched this human race

Here is true peace

Here my heart knows calm

Safe in your soul

Bathed in your sighs

Want to stay right here

Until the end of time

Sometimes, dreams do come true.

Categories: thinktime

Andrew Pollock: [life] Day 295: A big long play date

Fri 21st Nov 2014 22:11

I met Kelley at the first P&C meeting I went to, and she immediately took me under her wing, and later gave me a bit of a tour of the school, and some tips on Prep teachers and whatnot. I then proceeded to run into her nearly every time I went near the school.

She has a daughter, Chloe, starting Prep next year, and an older daughter in Year 3, and she's fairly well entrenched in the school community.

I thought it'd be good for Zoe to get to know Chloe a bit better, so she's one more person she knows at the start of school next year, so we had a play date at her house.

The girls seem to get along well, and Kelley's really nice. We have similar views in a lot of areas, and her husband works in IT security, so I think this could be the beginning of a beautiful friendship.

After lunch, due to the heat, we decided to bike down to the Colmslie Pool together. Kelley has a bike adapter trailer thing that couples a normal kid's bike to the back of hers, with the front wheel slightly elevated.

Zoe made me very proud at the pool, doing a kneeling dive into the water and swimming half the length of the indoor pool. Her swimming continues to progress in leaps and bounds.

We had a good time at the pool, and then biked back to school so Kelley could pick up her other daughter. We just hung out at the pool a bit early for swim class, and then biked home afterwards.

Sarah picked up Zoe, and then I headed out for the second Thermomix cooking class I've had to help out with. This one was a bit more fun for me because we had a great number of consultants on hand to share the workload, and I wasn't on washing up duties this time.

Categories: thinktime

Andrew Pollock: [life] Day 294: Babysitting play date, final Prep introductory day and an afternoon play date

Fri 21st Nov 2014 17:11

Wednesday was yet another full day. It's no wonder I'm feeling so tired, and have a backlog of blogging.

Mel had asked me if I could look after Matthew and Olivia for a couple of hours in the morning. Matthew and Zoe get along fabulously, and the time worked well, so I was happy to help out.

Zoe seems to be going through a bit of a nightmare phase at the moment. I'm sure the heat isn't helping. Zoe woke up with a nightmare about Smudge dying at 2am. Her room was 27°C at the time. 2am seems to be the nightmare time. I got her resettled within about half an hour. I really think I'm going to have to look into air-conditioning her bedroom sooner rather than later.

So I was a bit of a zombie when Mel dropped the kids off at 9am. Fortunately Matthew and Zoe just went off and played together, and Olivia was happy to just hang out with me. She's such a sweet little 2 and a half year old. She kept calling me "Lucy's Dad" or "Sophie's Dad" or something not quite right. It was very cute.

Mel was going to stay for lunch, and I'd been feeling adventurous, and made some hamburger buns and hamburger patties throughout the morning, with everyone running amok around me.

I improvised a bit on the hamburger buns, using a mix of baker's flour and whole-wheat flour and buckwheat. The result still turned out quite satisfactory.

After lunch, Zoe and I headed over to school for the final Prep introductory afternoon. Zoe wanted to walk today. It was a "best of" day for the fine motor skills activities, and Zoe was rather chuffed to get picked as a leader for the gross motor skills activities.

One of the Prep teachers (the one I hope Zoe gets next year) who had remarked on Zoe's timidity on the first day remarked today about what a different girl she was now.

Walking home, there were a ton of ibis on the football field we walk past, so Zoe had a great time running across the field chasing them all. She's getting a lot better about walking longer distances now.

Eva and Layla came over for a play with Tanya in tow after school, and the girls had a fun afternoon. A massive storm rolled in, and so I went and picked up Anshu from the ferry terminal. Once the storm abated, Tanya left with the girls, and then Sarah arrived to pick up Zoe.

Anshu tagged along with me to the P&C meeting. Not the most fun "date night", but I was glad to have another opportunity to attend a P&C meeting before the end of the school year.

Categories: thinktime

Michael Davies: Playing with the network

Fri 21st Nov 2014 13:11
I'm in the position of needing to improve my internet connectivity, so one of the first steps is to decouple all the things that provide the services I rely upon.



Stage one is to turn my modem into just an ADSL endpoint, removing any DHCP, NAT, and PPPoE termination from the device so that it has a single function.

Fortunately my nb604n ADSL modem has a nice easy-to-follow guide for taking it into bridge mode: http://support.netcommwireless.com/sm/videos/nb604n/nb604n-bridge-mode-setup-guide

Now onto greater things!

Categories: thinktime

Craige McWhirter: Craige McWhirter: Deleting Root Volumes Attached to Non-Existent Instances

Fri 21st Nov 2014 12:11

Let's say you've got an OpenStack build you're getting ready to go live with. Assume also that you're performing some, ahem, robustness testing to see what breaks and prevent as many surprises as possible prior to going into production. OpenStack controller servers are being rebooted all over the shop and during this background chaos, punters are still trying to launch instances with vary degrees of success.

Once everything has settled down, you may find that some lucky punters have deleted the unsuccessful instances but the volumes have been left behind. This isn't initially obvious from the cinder CLI without cross checking with nova:

$ cinder list +--------------------------------------+-----------+--------------+------+-------------+-- --------+--------------------------------------+ | ID | Status | Display Name | Size | Volume Type | B ootable | Attached to | +--------------------------------------+-----------+--------------+------+-------------+-- --------+--------------------------------------+ | 3e56985c-541c-4bdd-b437-16b3d96e9932 | in-use | | 3 | block | true | 6e06aa0f-efa7-4730-86df-b32b47e53316 | +--------------------------------------+-----------+--------------+------+-------------+-- --------+--------------------------------------+ $ nova show 6e06aa0f-efa7-4730-86df-b32b47e53316 ERROR (CommandError): No server with a name or ID of '6e06aa0f-efa7-4730-86df-b32b47e53316' exists.

It will manifest itself in Horizon like this:

Now trying to delete this volume is going to fail:

$ cinder delete 52aa706df17d-4599-948c-87ae46d945b2 Delete for volume 52aa706d-f17d-4599-948c-87ae46d945b2 failed: Invalid volume: Volume status must be available or error, but current status is: creating (HTTP 400) (Request-ID: req-f45671de-ed43-401c-b818-68e2a9e7d6cb) ERROR: Unable to delete any of the specified volumes.

As will an attempt to detach it from the non-existent instance:

$ nova volume-detach 6e06aa0f-efa7-4730-86df-b32b47e53316 093f32f6-66ea-451b-bba6-7ea8604e02c6 ERROR (CommandError): No server with a name or ID of '6e06aa0f-efa7-4730-86df-b32b47e53316' exists.

and no, force-delete does not work either. Here's my approach for resiolving this problem:

SSH onto your MariaDB server for OpenStack and open MariaDB to the cinder database:

$ mysql cinder

Unset the attachment in the volumes table by repeating the below command for each volume that requires detaching from a non-existent instance:

MariaDB [cinder]> UPDATE volumes SET attach_status='detached', instance_uuid=NULL, \ attach_time=NULL, status="available" WHERE id='3e56985c-541c-4bdd-b437-16b3d96e9932'; Query OK, 1 row affected (0.01 sec) Rows matched: 1 Changed: 1 Warnings: 0

Back on your OpenStack client workstations you should now be able to delete the offending volumes:

$ cinder delete 3e56985c-541c-4bdd-b437-16b3d96e9932

Happy housekeeping :-)

Categories: thinktime

linux.conf.au News: Funding Announcement

Fri 21st Nov 2014 10:11

AUCKLAND, New Zealand – Friday 21st November 2014 – linux.conf.au 2015 Organisers are proud to announce our funding programme!



InternetNZ Diversity Programme

LCA 2015 and InternetNZ are proud to support diversity. The InternetNZ Diversity Programme is one way we ensure that LCA 2015 continues to be an open and welcoming conference for everyone. Together with InternetNZ this program has been created to assist under-represented delegates who contribute to the Open Source community but, without financial assistance, would not be able to attend LCA 2015.

For more information please see our funding registration page.



About linux.conf.au

linux.conf.au is one of the world's best conferences for free and open source software! The coming linux.conf.au; LCA 2015 will be held at the University of Auckland, New Zealand from Monday 12 January to Saturday 16 January 2015. LCA 2015 will be fun, informal and seriously technical, bringing together Free and Open Source developers, users and community champions from around the world. LCA 2015 is the third time linux.conf.au has been held in New Zealand. The first was in Dunedin in 2006 and the second was in Wellington in 2010.

For more information please visit our website

About Linux Australia

Linux Australia is the peak body for Linux User Groups (LUGs) around Australia, and as such represents approximately 5000 Australian Linux users and developers. Linux Australia facilitates the organisation of this international Free Software conference in a different Australasian city each year.

For more information see: http://www.linux.org.au/

Emperor Penguin Sponsors

LCA 2015 is proud to acknowledge the support of our Emperor Penguin Sponsors, Catalyst IT, HP and IBM, and our diversity sponsor Internet NZ.

For more information about our sponsors click below -

        

Categories: thinktime

Matt Palmer: Multi-level prefix delegation is not a myth! I've seen it!

Thu 20th Nov 2014 17:11

Unless you’ve been living under a firewalled rock, you know that IPv6 is coming. There’s also a good chance that you’ve heard that IPv6 doesn’t have NAT. Or, if you pay close attention to the minutiae of IPv6 development, you’ve heard that IPv6 does have NAT, but you don’t have to (and shouldn’t) use it.

So let’s say we’ll skip NAT for IPv6. Fair enough. However, let’s say you have this use case:

  1. A bunch of containers that need Internet access…

  2. That are running in a VM…

  3. On your laptop…

  4. Behind your home router!

For IPv4, you’d just layer on the NAT, right? While SIP and IPsec might have kittens trying to work through three layers of NAT, for most things it’ll Just Work.

In the Grand Future of IPv6, without NAT, how the hell do you make that happen? The answer is “Prefix Delegation”, which allows routers to “delegate” management of a chunk of address space to downstream routers, and allow those downstream routers to, in turn, delegate pieces of that chunk to downstream routers.

In the case of our not-so-hypothetical containers-in-VM-on-laptop-at-home scenario, it would look like this:

  1. My “border router” (a DNS-323 running Debian) asks my ISP for a delegated prefix, using DHCPv6. The ISP delegates a /561. One /64 out of that is allocated to the network directly attached to the internal interface, and the rest goes into “the pool”, as /60 blocks (so I’ve got 15 of them to delegate, if required).

  2. My laptop gets an address on the LAN between itself and the DNS-323 via stateless auto-addressing (“SLAAC”). It also uses DHCPv6 to request one of the /60 blocks from the DNS-323. The laptop puts one /64 from that block as the address space for the “virtual LAN” (actually a Linux bridge) that connects the laptop to all my VMs, and puts the other 15 /64 blocks into a pool for delegation.

  3. The VM that will be running the set of containers under test gets an address on the “all VMs virtual LAN” via SLAAC, and then requests a delegated /64 to use for the “all containers virtual LAN” (another bridge, this one running on the VM itself) that the containers will each connect to themselves.

Now, almost all of this Just Works. The current releases of ISC DHCP support prefix delegation just fine, and a bit of shell script plumbing between the client and server seals the deal – the client needs to rewrite the server’s config file to tell it the netblock from which it can delegate.

Except for one teensy, tiny problem – routing. When the DHCP server delegates a netblock to a particular machine, the routing table needs to get updated so that packets going to that netblock actually get sent to the machine the netblock was delegated to. Without that, traffic destined for the containers (or the VM) won’t actually make it to its destination, and a one-way Internet connection isn’t a whole lot of use.

I cannot understand why this problem hasn’t been tripped over before. It’s absolutely fundamental to the correct operation of the delegation system. Some people advocate running a dynamic routing protocol, but that’s a sledgehammer to crack a nut if ever I saw one.

Actually, I know this problem has been tripped over before, by OpenWrt. Their solution, however, was to use a PHP script to scan logfiles and add routes. Suffice it to say, that wasn’t an option I was keen on exploring.

Instead, I decided to patch ISC DHCP so that the server can run an external script to add the necessary routes, and perhaps modify firewall rules – and also to reverse the process when the delegation is released (or expired). If anyone else wants to play around with it, I’ve put it up on Github. I don’t make any promises that it’s the right way to do it, necessarily, but it works, and the script I’ve added in contrib/prefix-delegation-routing.rb shows how it can be used to good effect. By the way, if anyone knows how pull requests work over at ISC, drop me a line. From the look of their website, they don’t appear to accept (or at least encourage) external contributions.

So, that’s one small patch for DHCP, one giant leap for my home network.

  1. The standard recommendation is for ISPs to delegate each end-user customer a /48 (giving 65,536 /64 networks); my ISP is being a little conservative in “only” giving me 256 /64s. It works fine for my purposes, but if you’re an ISP getting set for deploying IPv6, make life easy on your customers and give them a /48.

Categories: thinktime

Matt Palmer: A benefit of running an alternate init in Debian Jessie

Thu 20th Nov 2014 17:11

If you’re someone who doesn’t like Debian’s policy of automatically starting on install (or its heinous cousin, the RUN or ENABLE variable in /etc/default/<service>), then running an init system other than systemd should work out nicely.

Categories: thinktime

Donna Benjamin: DrupalSouth - Call for sessions open!! (closes 30 Nov 2014)

Thu 20th Nov 2014 09:11
Thursday, November 20, 2014 - 08:49

DrupalSouth is the biggest Drupal gathering in the Antipodes.

We'll be at the Melbourne Convention and Exhibition Centre over three days in early March 2015. March 5-7 to be exact.

Find out more at the website

https://melbourne2015.drupal.org.au/

The call for sessions is open, and we're trying hard to get the word out wide and far, to whisper in new ears, and encourage people of all sorts to share their ideas for sessions so we can create a truly wonderful, inspiring, engaging and fun program for this conference!

For those who may not know, Drupal is an open source content management system. It's used by people and organisations all around the world, for all sorts of web sites. It's also being used as back end application framework for mobile apps! It's amazing what Drupal can do.

Drupal events are the heart and soul of the community that makes Drupal. Bringing people together drives the project forward, and forges friendships.

But we're also part of the wider web. So we want to hear from all sorts of web specialists, not just Drupalists.

Please, submit a session, or simply help us spread the word. The deadline is looming and won't be extended. Get that proposal in by 30 November 2014. https://melbourne2015.drupal.org.au/program/session-submission

Categories: thinktime

linux.conf.au News: Speaker Feature: Andrew McDonnell, Jim Cheetham

Thu 20th Nov 2014 07:11
Andrew McDonnell Reverse engineering embedded software using Radare2

1:20pm Thursday 15th January 2015

Andrew McDonnell is a professional software engineer with two decades experience, having spent many years before that hacking code after receiving a Commodore 64 for Christmas at age 12. He has significant experience programming in C++, Java and Python and a multitude of scripting languages. Outside of family and work he sometimes has time to play with his collection of 8-bit and PC/XT-vintage computers; computing and electronics has always been his passion. He intermittently maintains a blog at http://blog.oldcomputerjunk.net sometimes posting how he solved a problem in the hope it may be useful to someone else.

For more information on Andrew and his presentation, see here. You can follow him as @pastcompute and don’t forget to mention #lca2015.



Jim Cheetham OneRNG - An Open and Verifiable hardware random number generator

1:20pm Thursday 15th January 2015

Jim works in Information Security, and has a long background in Unix/Linux and Open Source/Free software systems.

For more information on Jim and his presentation, see here. You can follow him as @onerng and don’t forget to mention #lca2015.

Categories: thinktime

Jonathan Adamczewski: Unquestionably bad

Wed 19th Nov 2014 18:11

Question 5:

Consider the following 6 data structures:

  • Stack
  • Queue
  • Hash table
  • Doubly-linked list
  • Binary search tree
  • Directed acyclic graph

Using these as the subject matter, construct 6 really good puns.

 

Answers:

After receiving a range of questions from different sources, I was unsure which to answer first — I was stack as to where to begin. And so because this was the last question that I received, it became the first that I answered.

Don’t get me wrong — I did appreciate the question. The capacity of my gratitude is, theoretically, unbounded. Thanqueue.

We have a cuckoo aviary. I keyp a record of each birth in a hatch table.

I noticed that I was leaning to one side. I spoke to a physician about it — he told me I was overweight because I was eating too much bread. My list, it seems, is linked to my dough-belly.

On a school trip to a pickle factory, my daughter went missing. I was able to climb the brinery search tree and spot her, though it took longer than I had hoped due to my poor balance.

While out walking, I deflected a cyclist’s gaffe, knocking him aside as he rode the wrong way down a one-way street. I looked down my nose at him and gave a topological snort to help him on his way.

 

The reader may decide whether the answers satisfy the requirements of the question.

Categories: thinktime

linux.conf.au News: Speaker Feature: Katie McLaughlin, Andrew Bartlett

Wed 19th Nov 2014 04:11
Katie McLaughlin Before All Else, Be Graphed

3:40pm Wednesday 14th January 2015

Katie is a part of the Engineering team at Anchor Systems, working to improve *all* the things. She has a history of enterprise development and Windows system administration, but has been successfully converted to the ways of the penguin in recent years.

When she's not changing the world, she enjoys making tapestries, cooking, and yelling at JavaScript and it's attempts at global variables.

For more information on Katie and her presentation, see here. You can follow her as @glasnt and don’t forget to mention #lca2015.



Andrew Bartlett Pushing users into the pit of success - stories from the Samba 3 -> Samba 4 transition

23:40pm Thursday 15th January 2015

Andrew Bartlett is a Samba Developer currently employed by Catalyst in Wellington, NZ. Andrew has been developing Samba since 2001, and has had a strong focus on the Active Directory DC project for the past decade or so. He is passionate about authentication systems and making Samba a great, interoperable alternative to the dominant implementation from Microsoft.

For more information on Andrew and his presentation, see here.

Categories: thinktime

Andrew Pollock: [life] Day 293: Kindergarten, Property Occupations Act Roadshow

Tue 18th Nov 2014 22:11

Zoe woke up at some point in the night. I have a vague recollection of a conversation with her, and lacking the willpower to get out of bed to put her back to bed in her own bed. The next thing it was 5:30am and she was sleeping sideways in bed with me.

Despite all that, I felt more rested this morning, which was good. We managed to get going quite early as well, without really trying. I had to be out at the Sleeman Sports Complex at 9am for a roadshow by the REIQ about the new Property Occupations Act, which kicks in on December 1 to replace the current Property Agents and Motor Dealers Act.

It also rained this morning, which doubly made it necessary to go to Kindergarten by car. We were actually running so early that we got there before opening time, which I've only managed to do a few times all year.

I ended up getting to the Sleeman Sports Complex about 15 minutes early. It was fun playing "spot the real estate agent's car".

I didn't learn anything earthshattering in the briefing, but it was useful to get fully up to speed on the new legislation. I just hope that being half way through a course that has covered the old legislation isn't going to be a problem.

I got home from that with enough time to just chill out for a bit (I ended up doing a bit of tinkering) before it was time to pick up Zoe. The weather was still a bit questionable, so I picked her up in the car.

Zoe wanted to watch Megan's tennis lesson again, and I had to be at home for a 3pm video chat, so I left her with Jason and popped home.

After my video chat, I went around to Jason's and helped with a bit of painting before heading home to start on dinner.

I had enough for Jason, Megan and Megan's little sister, so they came over for dinner as well.

I got Zoe down to bed at the normal time, but her bedroom is ridiculously hot. I'm not terribly confident I won't get another uninterrupted night's sleep.

Categories: thinktime

Jeremy Visser: One week with the Nexus 5

Tue 18th Nov 2014 18:11

My ageing Motorola Milestone finally received a kick to the bucket last week when my shiny new Nexus 5 phone arrived.

Though fantastic by 2009 standards, the Milestone could only officially run Android 2.2, and 2.3 with the help of an unofficial CyanogenMod port. Having been end-of-lifed for some time now, and barely being able to render a complex web page without running out of memory, it was time for me to move on.

I was adamant that I would only buy a Nexus phone. Vendors that ship OEM customisations to the Android image are the spawn of the devil, and I wasn’t interested in buying a device that would be abandoned after the next model came out. After all, I’m not a gadget person. This is a big deal for me, and I hope this phone lasts me four years, just like my Milestone did.

Can I just say how fantastic the hardware is. The case is much more aesthetically pleasing than most of the Android phones I’ve had the (dis)pleasure of trying out, the screen is beautiful, and the software keyboard is smooth, accurate, and responsive.

On the screen. I think five inches is the maximum size I can cope with. I must say, being a person with small hands, I am not a large screen person. I can only just reach the opposite X axis with my thumb, and I need to reposition my hand (or use a second hand) to reach the opposite X and Y points. So yes, that’s why I didn’t get a Nexus 6.

On the software, I am thoroughly impressed by Android 4.4. Thoroughly. Google have done just about everything right. Nearly anything bad I have ever said about Android in the past either doesn’t apply to Android 4.4, or only applies to customised OEM builds.

Everything I would have wanted to root my phone to do previously is totally unnecessary.

Out of the box, FLAC audio and IPsec Xauth VPNs (main mode only, not aggressive mode) are supported. Just by installing an app, I can get my strongSwan IKEv2 VPN working.

Interestingly enough, this phone constantly bombards me with security warnings as a result of the fact that I have installed my own certificate authorities. I think this is an interesting development, and is probably a proactive stance against the possibilities that ISPs and/or governments may encourage you to allow them to perform SSL man-in-the-middle attacks on your connection in future for tracking and advertising purposes.

Hopefully warnings appearing on users’ phones worded such as “your network may be monitored” is enough to scare off those who may have such evil intentions.

The phone is amazingly responsive. Not only that, it multitasks with ease, and the user interface is smooth.

One minor criticism is that Google Maps appears to be capped at around 15 frames per second. This is odd, as similar apps such as Google Earth run at a much more pleasing framerate.

It is probably an unfair comparison, as the Nexus 5 is so much higher specced, but overall I am finding the device much faster and more responsive (and therefore I’m more likely to grab it and use it for quick tasks) than my iPhone 4S.

Ever since the release of iOS 7, my iPhone has been frustratingly slow and unstable. Sadly, apps crashing due to low memory conditions are an almost daily occurrence.

It is unclear to me whether this is a deliberate decision by Apple in order to make their later model iPhones look better, but I find it fascinating that I find my Nexus 5 being more pleasurable to use than my iPhone 4S. Something I would not have thought possible a fortnight ago.

I’m so impressed by Android 4.4 that I’m almost dreading the impending 5.0 upgrade in the fear that Google will “do an iOS 7″ — i.e. make the device significantly less useful by making it slower and less stable.

Categories: thinktime

linux.conf.au News: Speaker Feature: Marc Merlin, Jussi Pakkanen

Tue 18th Nov 2014 07:11
Marc Merlin Why you should consider using btrfs, real COW snapshots and file level incremental server OS upgrades like Google does

11:35am Wednesday 14th January 2015

Marc has been using linux since 0.99pl15f (slackware 1.1.2, 1994), both as a sysadmin and userland contributor. He has worked for various tech companies in the Silicon Valley, including Network Appliance, SGI, VA Linux, Sourceforge.net, and now Google since 2002, both a server sysadmin and software engineer.

He has done hacking in various areas like mail with exim, mailman, SpamAssassin and SA-Exim, as well as maintained various linux distributions at Google and elsewhere, and given talks about some of those projects, and others at linux conferences since 2001 (LCA, OLS, Linuxcon, Usenix/LISA).

For more information on Paul's presentation, see here.



Jussi Pakkanen Making build systems not suck

2:15pm Thursday 15th January 2015

Jussi got his doctoral degree in computer science in 2006. Since then he has worked in various problem fields including mail sorting. He is currently employed by Canonical where he has worked on various parts of Ubuntu desktop and phone. In his free time he dabbles with drawing, creating computer games, photography and whatever else might catch his fancy.

For more information on Jussi and his presentation, see here. You can follow him as @jpakkane and don’t forget to mention #lca2015.

Categories: thinktime

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