Linux FormatJune 2017的目錄

Jonni Bidwell I’m a little sad, but I don’t know exactly why. I use Gnome every day and always found Unity to be a bit clumsier/clunkier. I suppose that I thought it was more beginner friendly, and now a lot of people that have never encountered Gnome 3 will, come to 18.04 and suddenly find themselves in terra incognita. Neil Bothwick I think many users may be disappointed. Unity is already using Gnome3 technology so I think the ‘new’ desktop will be a lot more like Unity than the old Ubuntu desktop. Had they gone with Cinnamon things would have been different. But I’m a KDE diehard so what do I know? Les Pounder When Unity was first released I fell out of love with Ubuntu. For years I loved…

One of the biggest questions hanging over Canoncial’s abrupt dropping of Unity is what will happen to the desktop environment – and the versions of Ubuntu that are currently running it. For seven years Canoncial has been concentrating on Unity after dropping GNOME, and since Ubuntu 11.10, Unity has been the default desktop for the distro. For the time being, it looks like not a huge amount will change. Unity hasn’t had any major updates for a while now, instead getting a few minor adjustments to make sure it continues to work. Unity should still get some updates, then, in the future, to make sure people using it aren’t left completely unsupported. As Mark Shuttleworth stated, “Unity 7 packages will continue to be carried in the archive. I know there…

“Ubuntu’s decision to move back to a GNOME-based desktop will have ramifications for years to come. For user experience, unifying the desktops means combining forces and eliminating duplicated effort. For developers, a lot of the differences in APIs such as indicators, menus, and scrollbars could now come to an end, making Linux an easier target for ISVs. Not to mention that we are back to only supporting two window systems: Wayland and legacy X11. With Ubuntu following Fedora’s lead in shipping Wayland-based GNOME for 18.04, all major distros will reap the benefits of the work done to Wayland, EGL, and Vulkan across the board. And we’ll undoubtedly see more focus on improving and extending Wayland. But you may be surprised with continuity, and just how much of the graphics infrastructure…

Find and join a LUG Alpinux, le LUG de Savoie Meet on the first and third Thursday of the month at the Maison des Associations de Chambéry. www.alpinux.org Bristol Hackspace Studio G11, 37 Philip Street, Bedminster, Bristol, UK, BS3 4EA. http://bristol.hackspace.org.uk Surrey and Hampshire Makerspace Tuesdays and Fridays at the Boileroom in Guildford. www.shmakerspace.org Lancaster and Morecambe Makers Unit 5, Sharpes Mill, White Cross, Lancaster, Open Night on Wednesday evening 6:30pm till late. www.lamm.space Hull Raspberry Jam Malet Lambert School, Hull. Every other month. See their Twitter account. https://twitter.com/hullraspjam Preston Hackspace 28a Good St, PR2 8UX. Open night is 2nd Monday of the month, 7pm. http://prestonhackspace.org.uk Huddersfield Raspberry Jam Meet every month at Huddersfield Library, usually 4th Saturday. Huddersfieldraspberryjam.co.uk North Kent Raspberry Pi User Group Every two weeks at Medway…

This is another one of those parameters that really isn’t a factor when choosing one of these candidates. That’s because all the distributions on test here use the distribution-independant Calamares installer. Calamares is actually a framework that the distributions can customise as per their target users. The installer is pretty intuitive and visually appealing and gets the job done without too much fuss. Its partitioning feature supports both manual and automated partitioning tasks. It also includes a very convenient Replace Partition option that allows you to reuse a partition for hopping distributions. That said it’s best for simple straightforward installations and doesn’t yet support advanced setups like RAID and LVM partitions. One obvious difference between the implementations of the Calamares installer across the distributions is purely cosmetic. The other difference…

There’s no dearth of mainstream and smaller distros with KDE desktops. The mainstream ones include Kubuntu, OpenSUSE and Mageia all of which use a heavily modified KDE desktop. You can try KDE atop Debian, and Linux Mint, Fedora’s KDE flavour uses a virtually unmodified KDE desktop or Korara’s KDE is similar but with a larger number of default apps. The Debian-based SparkyLinux and Arch-based Antergos are two smaller projects. You can also experience KDE straight from the developers with KDE Neon. While the Ubuntu-based distro includes an installer, its developers only intend it as a demonstration platform and not an everyday distro. If you are not averse to non-Linux operating systems, several BSDs also use the KDE desktop including TrueOS, FreeBSD, and OpenBSD.…

Snaps (or snappy packages or whatever you want to call them) and the tooling for dealing with them, have been available in Ubuntu since 16.04. They solve a number of shortcomings of current packaging methods. First and foremost, thanks to containers being all the rage they are installed in isolation to the rest of the system. So even if you install a rogue snap, it’s very limited in the amount of damage it can do. Snaps are also, in one sense anyway, much more portable than traditional .deb packages. They can be installed on any distribution supporting snaps, since they include all of their dependencies. This of course has the adverse effect of making them larger than traditional packages, but also makes the packaging process far more simple – developers…

The open source Nvidia driver, Nouveau, is a remarkable project. Unlike AMD, Nvidia has contributed very little in the way of free code for its desktop cards. Back in the day there was a free driver called nv which contained code so obfuscated that many a developer went mad just trying to parse it (joke). So the Nouveau project was set up in 2005 to reverse engineer the hardware and write drivers that could be free, maintainable and sanity-preserving. Nouveau is the default driver for Nvidia hardware and generally works well, insofar as users generally don’t find themselves booting to a black screen. But if you need performance, Nouveau is not likely to be much help. The reason is that these cards boot in a low-power state, and without using…

ON THE MAKER COMMUNITY “It plays a big part. Everyone helps each other with perspectives and advice.” Robin is a fresh face in the maker community. He is at Maker Faire UK to demonstrate his first project, a keypad that can be programmed to perform multiple tasks at the push of a button. But what makes this project different to others is that it is programmed using a block interface. Linux Format: Hi Robin, thanks for taking the time to talk to Linux Format. So can you tell the readers who you are? Robin Hartley: Hi, I’m Robin and I am studying for a Masters degree in Chemical Engineering at the University of Sheffield. LXF: So you are not an Electronics Engineer? RH: No, electronics and ‘making’ is just a…

“In this release MATE got rid of the historic (yet widely used) GTK2 library.” Desktop environment MATE Version: 1.18 Web: https://mate-desktop.org The world of Linux desktop environments has been a matter of passionate discussion and fierce online battle for decades, yet there is one thing that didn’t change dramatically over the years. We are alluding, of course, to MATE, a successor to the once-famous and widely used GNOME 2 desktop. If we cast an eye back a few years, we see GNOME 2 as a standard desktop for the first Fedora Core releases, Novell Enterprise Linux, OpenSolaris and more, with a focus on enterprise-class Unix-based desktops. The curious bit is that MATE looks and behaves exactly the same as GNOME 2, offering pleasant updates and support that bring it on…

Ten dollars can buy you a lot of computer – now it even comes with Wi-Fi and Bluetooth. Let that sink in for a moment. For such a low amount of money we can add the Internet of Things (IoT) to our projects and embed a Raspberry Pi into even the smallest of projects. When the Raspberry Pi first burst onto the scene in 2012, a development board used to prototype projects would cost around $150. But the Raspberry Pi disrupted the market and reduced that price to $35, and this price has remained synonymous with the Pi. The Model A reduced the price further, but it wasn’t until the Pi Zero in late 2015 that we saw another disruption to the market. $5 for a computer is ludicrous. We…

The term LED, short for Light Emitting Diode is quite ambiguous. There is the humble LED, used to signify that a device is on and to say “hello world” when building your first circuit, but there are many others. We used Neopixels, a brand name for WS2811/12 LEDs. These super bright LEDs run from a 3.3V or 5V power supply and use carefully timed pulses to communicate the state of LEDs. Now as we learned in the tutorial, this causes issues as we have to use the GPIO pins, specifically a pin that can perform PWM, and this forced us to disable analogue audio output. But there are other LEDs that we can use instead of the Neopixel, and this is in the form of the APA102 series. These LEDs…

When the calendar is on your wall, the cursor can look untidy, especially if you are using a touchscreen. A handy app named Unclutter can hide the cursor except when it’s being moved or you’re touching the screen. Open Terminal on your Pi (or connect via SSH) and run the command: sudo apt-get install unclutter In case the Pi crashes and you’re forced to reboot, it’s also best to have Firefox programmed to open automatically, saving you the trouble of reconnecting a keyboard and mouse. Open Terminal on your Pi (or connect via SSH) and run the command sudo nano /etc/xdg/lxsession/LXDE-pi/ autostart . Scroll to the bottom of the window and add the line @firefox-esr . Press Ctrl+X, then Y, then Return to save your changes. Finally, to make sure…

Our expert Nick Peers has been playing around with computers for over 30 years, and has been dabbling with Linux for the best part of a decade. Ubuntu’s default terminal is the Gnome-Terminal, and one of its lesser known features is support for profiles. Profiles are a collection of terminal settings, including profile name, font and background colours, and scrolling. In addition, profiles can be set to run a specific command or shell on startup, launch to a specific screen and even connect to a remote computer via SSH. This flexibility makes it easy to see why a single user might want to develop more than one profile for using the terminal – you may, for example, regularly administer another PC via SSH, such as a headless Pi Zero running…

Our expert Afnan Rehman is a student, Linux tinkerer, and general computer geek who breaks everything first so that you don’t have to. Have you ever wanted to build your own router without going through the hassles of creating your own iptables and network rules from scratch (the way we have to on page 84)? It’s possible to get the functionality and performance you’re looking for without putting in as much work. The solution is pfSense, the open source network firewall/router software distro based on the FreeBSD OS. pfSense is used in many different applications from home routers to business solutions and is well regarded in the community for its reliability and versatility. Assuming you have the hardware for it, which is quite modest by any standards, pfSense can be…

Our expert Mihalis Tsoukalos is a Unix administrator, a programmer, a DBA and a mathematician who enjoys writing articles and learning new things. HAProxy, which stands for High Availability Proxy, is a Load Balancing reverse proxy for TCP and HTTP applications. This tutorial will use HAProxy in combination with MySQLto illustrate its load balancing capabilities. However, HAProxy can also be used with other TCP servers such as Apache and Nginx. Please do make backup copies of every file you make changes to, so you’ll be able to get back to your initial configuration more easily. The main reason for this is that software that deals with web sites and database servers can make them inaccessible to clients when configured incorrectly, and this will provide a quick fix. Getting and installing…

Our expert John Lane trusts that GnuPG will trust him to trust that key that trusts the web of trust... PGP means “Pretty Good Privacy”. Not perfect then, but, perhaps, a pretty good way to encrypt messages and other documents or to prove that they have not been altered by anyone. If you can understand its so-called “Web of Trust”, that is. Many Linux users will at some point encounter the Gnu Privacy Guard (GnuPG), an implementation of the OpenPGP standard, but getting the most from it requires untangling that web. You use someone’s key to send them an encrypted message or document, or to verify the authenticity of a signed message or document that they’ve sent you. But anybody can create a key for any identity, so before using…

Our expert Afnan Rehman is a student, Linux tinkerer and computer geek who breaks things first so you don’t have to. It’s time to take charge of your network. As individuals in the unfortunate situation of being both attracted to technology and prone having it fail on us, we’ve gone through our fair share of consumer routers. Hunting for this year’s replacement we stumbled on a new idea, that you could build your own using Linux, with full control of the functionality and settings. What a novel idea! We immediately retrieved a PC from the LXF dungeon and set to work. The idea of building a router is not completely new, but is growing in popularity among tech enthusiasts as a way to squeeze every last bit of performance out…

Our expert Thomas Rumbold has a background in web development, application and technical writing. These days he’s Production Director at web design agency, Onespacemedia. A web framework (or web application framework) is a software framework that is designed to support the development of websites and online software applications – including web services, web resources and web APIs. Web frameworks aim to alleviate the overhead associated with common activities performed in web development by providing a series of tools designed to simplify and accelerate the technical development process for web developers. So, what is Django, and what is it good for? Simply put, Django is a Python web framework designed to enable website and web application developers to build and deliver complex projects quickly, securely, and to a consistent, ‘clean’ style.…

which has enabled users to trade over €100m, an online at-home learning platform, COSMOS, for children’s science education charity Cambridge Science Centre, and ongoing projects for Imperial Innovations which ensure that their digital presence reflects their status as champions of innovation. Onespacemedia is a Cambridge-based web design and development agency specialising in Python and working with some of the most innovative companies in science and technology. We use Django to build the vast majority of our sites and apps. Recent projects include a fintech application for MoneyMover…

Netbeans offers excellent editors for all sorts of programming. There are versions for Java, PHP, HTML / Javascript and C/C++ just to name a few. Go to https://netbeans.org and download. There are many versions, but the PHP version will work for Lamp web development. You have options for x86 and 64-bit versions too. Netbeans will need Java JDK 8 in order to work. You can download and install it via command line or from: www.oracle.com/technetwork/java/javase/downloads. After the download, you can right click on the netbeans-8.2-php-linux-x64.sh file, select permissions and allow it to run as an executable, then close. Now, you just have to right-click on it and select Run. At this point, you just follow simple, typical GUI installation instructions. After installation, there will be a Netbeans icon on your…

We know there’s a collective roll of the eyes from many regular readers when we run our (bi)-annual Ubuntu release covers. But there’s no escaping the sales boost every orange-soaked cover gains on the yearly 04 release schedule. It’s actually heartening to see so many people looking forward to, or at least welcoming, the release of a new version of Ubuntu by rushing out and snapping up our little magazine. The truth is that Canonical, and its prime distro Ubuntu, remains a key driver for Linux both on the desktop and in the enterprise world. Red Hat and SUSE certainly have made their own mark in enterprise, but Canonical is seeing wins in the telephony industry, ‘cloud’ market and the emerging IoT world of devices from Pi-like boards to self-driving…

At the beginning of April when Mark Shuttleworth announced Canonical’s plans to drop Ubuntu Phone and Unity, he was known as the founder of Canonical and ex CEO. Less than a month later, he was once again the CEO. This follows the announcement that the (then) current CEO of Canonical, Jane Siber, was standing down. In a blog post (https://insights.ubuntu.com/?p=66110), Siber wrote that “We’re now entering a new phase of accelerated growth at Canonical, and it’s time to pass the baton.” Siber insisted that this was not a sudden decision. She had “originally agreed to be CEO for five years and we’ve extended my tenure as CEO by a couple of years already”. Siber will remain CEO for the next three months, with Shuttleworth replacing her in June. Siber will…

RANCHEROS 1.0.0 A major release for the minimalist distro that focuses on running Docker containers has emerged. The idea behind the distro is to keep the footprint of the OS as small as possible, so your machine can commit as many resources as possible to the containers. According to the official blurb: “Key features of RancherOS include: minimalist OS – eliminates the need for unnecessary libraries and services; automatic configuration – simplifies OS configuration by using cloud-init to parse the cloudconfig files from multiple data sources; simple setup – runs services inside containers orchestrated using Docker Compose service files, making setup as simple as running a Docker container.” To find out more, and to download, head to http://rancher.com/press-release-rancheros-ga. KAOS 2017.04 The newest version of KaOS has been released in time…

Firewalls Don’t worry, I’m not writing for a USA edition, the UK version works just fine. I was wondering if you could cover my favourite Linux firewall, either in a firewall Roundup, or as part of an OpenSuse review? I find the SuSEfirewall2 to be very easy to use, using either Yast or editing the config file directly, and I can get much more granular with the rules than I can with most of the other firewalls out there. Chris Lucht, CT USA Neil says: As you might have noticed we ran openSUSE Tumbleweed with LXF222 and we managed to squeeze the entire 4.7GB of the full openSUSE on to LXF220! So hopefully that will help slake people’s thirst for the green geko for a while at least. I have…

The primary mode of dispensing help and handling support queries for all the distributions on test here is the humble forum board. Some of these, such as Chakra’s, are fairly active and Manjaro is unique in this Roundup in that it hosts multilingual forum boards. Maui has a blog for announcing new releases. There’s also a Readme icon on the desktop of both Maui and Netrunner. While the one in Maui displays some brief information about the current release, Netrunner’s lists information that’ll come handy post-installation and the distribution also has an illustrated installation guide. Chakra includes an illustrated Beginner’s guide as well, and a wiki with articles to help install and manage the distribution. However, note that while many articles are fairly detailed, some, such as the one on…

“What this springtime is really all about is the new Ubuntu release.” Spring is here, and that can mean only one thing. Actually it could mean one of many things – hayfever, youthful romances blossoming in the quad, chthonic Walpurgisnacht celebrations on the hill – but those inconveniences aside, what this springtime is really all about is the new Ubuntu release, numbered and named 17.04 and Zesty Zapus respectively. We’ve scrambled to get it onto our coverdisc, moving press deadlines right down to the wire, pleading with Polish disc replicators and forcing this writer to stay up late drinking gallons of coffee. While the non-LTS releases aren’t recommended for production systems, they are thoroughly tested and great for showing the direction next year’s LTS will take. Users of previous releases…

The latest GNOME release doesn’t have too many user-facing changes, although it does feature Night Light, which tweaks your display temperature to reduce the amount of blue light it radiates during night hours. By making the display warmer at night time, eyestrain and tiredness should be reduced. Such programs have been around for a while, for example there’s the cross-platform but closed source f.lux, or the open source Redshift. People, in particular the people that write for Linux magazines, are spending more and more time looking at screens well into the small hours and their retinal health and circadian rhythms are suffering. So it’s nice to see this functionality being incorporated natively into GNOME now, if nothing else it’s one less out-of-place icon in the system tray. Also Redshift doesn’t…

ON INDEPENDENT MANUFACTURING “I don’t want to go through the whole venture capital system and go to China.” Adrian is well known in the maker community, in fact he wrote the book on designing products for the Internet of Things. He’s a keen advocate of independent manufacturing and scaling hobby projects into commercial products. LXF: Hi Adrian, thanks for taking the time to talk to LXF, can you tell the readers a little more about yourself? Adrian McEwen: I mostly describe myself as someone who connects strange things to the internet. This could mean a bubble machine connected to Twitter, or a sensors monitoring a wave energy machine sat in the English Channel that send their data over 3G for analysis. My work is really varied and interesting. I am…

The glxgears utility is often mentioned in conjunction with testing OpenGL functionality. If you’ve never encountered it before (and indeed even if you have) it renders three cogs spinning in a way that is relatively pleasing to the eye. It also emits FPS data to stdout, but since most configurations lock framerate to the monitor’s refresh rate (so-called vsync) this generally just displays something very close to 60fps. It doesn’t take much GPU (or even CPU power, relatively speaking) to maintain this refresh rate nowadays, so unless you like cogs glxgears has dubious benchmarking value. However, if you’re using drivers built on the Gallium framework (ie, Nouveau or AMD’s open source drivers, not Intel or proprietary drivers) you can use glxgears to test a little-known feature, the Gallium Head Up…

Our expert Nate Drake is a freelance technology journalist who specialises in cybersecurity and retro tech One staple in films such as Back to the Future and Time Cop is that everyone has a handy digital-planner panel in their living room showing their appointments for the day. While we already have calendars on our smartphones and tablets, but now, thanks to the Raspberry Pi, it’s possible for you to have an economic wall-mounted calendar in your home or office too. Given that we have just tacitly admitted we could use the calendar app on our phones instead, is this project merely a novelty, or are there any advantages to it? Well, there’s always the look of the thing. A calendar mounted on a wall can certainly be more aesthetically pleasing…

Our expert Jason Cannon started his career as a Unix and Linux System Engineer in 1999. Since then he’s used his skills at such companies as Xerox, UPS, Hewlett-Packard, and Amazon. This lesson will cover how to compare the contents of files. If you want to compare two files and display the differences, you can use the diffcommand. The sdiff command or vimdiff. The diffcommand will display the difference between two files, while the sdiffcommand will display the difference with file1 on the left and file2 on the right. Vimdiffwill use the vimeditor to display the difference between two files. diff file1 file2 #compare two files sdiff file1 file2 #side-by-side vimdiff file1 file2 #within vim Here’s just the first line of output produced by diff. $ diff file1 file2 3c3…

You can easily change profiles without leaving your current terminal session – the obvious choice is to open the Terminal > Change Profile menu and select the profile you want. Doing so will instantly apply that profile’s settings to the current session. It won’t, however, run any custom commands assigned to that profile. You can also launch a new Terminal session from within the command line – note this will launch it in a new window (and is the equivalent of choosing File > Open Terminal): $ gnome-terminal --window-with-profile=<PROFILENAME> Replace <PROFILENAME> with your chosen profile name (which is case sensitive. If the profile has any spaces in it, precede this with a backslash character – for example, Mopidy\ server ).…

Hopefully by the end of this tutorial, you will have a working router with pfSense running and a web interface that can be easily accessed through a client computer. There are a few final suggestions we have for you once you reach this point. Firstly, once you reach the end, there will most likely be absolutely no need for you to check the display directly from the computer running pfSense. If you had it hooked up to a monitor, feel free to re-purpose that monitor for some other use. Even if you need to restart the router, that can all be handled from the web interface, just as if it were a consumer router that you would control from a web interface. Since this router does not have wireless capability,…

hatopis an interactive ncurses client for HAProxy whereas haproxyctlis a utility for managing HAProxy from the command line. Neither of them is required for HAProxy to work but they can make your life easier should you decide to install them. On Debian and Ubuntu Linux systems you can install them as follows: # apt-get install hatop haproxyctl haproxyctlallows you to quickly administer and overview HAProxy with its handy command line options: $ sudo haproxyctl show health $ sudo haproxyctl show stat The first command allows you to quickly check the status of HAProxy whereas the second command returns counters for each proxy and server. Should you wish to learn more about haproxyctl, you can visit its man page. The image on the final page shows the hatop utility in action.…

You can set up a separate GnuPG configuration if you want to follow our examples without affecting your own GnuPG setup. You can either append a --homedir” option to each gpg command or set GNUPGHOME . Both point to a directory where GnuPG should maintain its configuration, including your sandbox key-ring. Going with the latter option, here’s how to set up a new sandbox: $ export GNUPGHOME=~/sandbox.gpg $ mkdir -m 700 $GNUPGHOME $ gpg --gen-key Remember you’ll need to unset “GNUPGHOME” or use “--homedir=~/.gnupg” to access your real configuration.…

Once you’ve rebooted after editing your network interfaces file the first time, you may notice that your internet connection has gone bad and you are no longer receiving an active connection. You may notice a message over the network interface saying “device not managed”. This is because you altered the network configuration in the /etc/network/interfaces for your two Ethernet ports. You can fix this by editing the network manager configuration file. You can open the /etc/NetworkManager/NetworkManager. conf file and change the line that says managed=false to true . Save the file and restart the network manager with the following: $ sudo service network-manager restart Alternatively, I recommend setting up a wireless connection here or just make sure you had everything downloaded beforehand. If you need to reverse this, simply roll…

There are four files that are generated when you run startproject , they are manage.py, settings.py, urls.py and wsgi.py. The manage.py file is a replacement for the django-admin command we used earlier, it’s your main entry point into your application and it’s what we use to run any management commands related to our project, for example creating an admin user. It’s very rare that you’ll need to edit this file. The settings.py file contains all of the settings needed for our project, such as the name of the project, the URL it will live under and so forth. We won’t be editing it as part of this process, but it’s worth having a look through just to see what’s in there anyway. The file urls.py is the base routing file…

Our expert Kent Elchuk has been a professional writer, web developer and hobbyist for quite some time. His works range from simple websites to custom web applications systems for a number of colleges. One of the great reasons to use Linux is that it makes web development an easy process. When we say easy, we mean it makes it free and easy to build and test websites and web applications. Since so much of the web is powered by websites hosted with Linux, including giants like Google and Facebook, using Linux for building makes it convenient to set up a solid building and testing environment. If that does not convince you, maybe the source at https://en.wikipedia.org/wiki/Goobuntu will, which explains that 10,000 employees at Google use Goobuntu. A flavour of Ubuntu,…

Linux on MacBooks Smash your old MacBook and Linux together to gain the best OS running on the best hardware. Your own Darknet Fire up your own secret and secure Darknet-built websites, so you can share secret and secure things. Key madness! We look at security through Yubikey TFA, and staying secure online for chats and more with Keybase. Contents of future issues subject to change – we might be too paranoid to get out of bed.…

It may come as little surprise, but a security researcher has uncovered 40 unknown zero-day vulnerabilities in Tizen, the mobile operating system that runs on a number of Samsung devices. According to the person who found the vulnerabilities, Amihai Neiderman, “It may be the worst code I’ve ever seen... You can see that nobody with any understanding of security looked at this code or wrote it. It’s like taking an undergraduate and letting him program your software”. All the vulnerabilities Neiderman found would give hackers the ability to perform remote-code executions to hijack software running on other devices. Let’s hope these findings prompt Samsung to take the security of its smart devices more seriously. http://bit.ly/LXF224tizen The results of Stack Overflow’s annual developer survey are in (see https://stackoverflow.com/insights/survey/2017) with over 64,000…

“Open source networking has come a long way in the past five years. In this time, it has evolved from a disaggregation of networking components at all levels of the stack, to production-ready components matured and deployed in various production networks. This year, open source is poised to enter its third phase of development: production-ready end-to-end solutions. With this comes fresh challenges, the most glaring of which is the current fragmentation in the industry. For open source to move forward, harmonisation needs to take place across the stack. This will give rise to common frameworks between the different open networking projects that will, in turn, dictate their interoperability. Without this crucial step, the mass adoption of open source solutions in the carrier network space will prove impossible. How can we,…

Let me just say I totally agree with John Wagner’s letter “Puzzling” in LXF219. Learning a new language can be pretty dry if you don’t have, or can’t think of a target application. Resolution of a puzzle, solving a mathematical challenge or simulating a ‘dynamic’ problem would be ideal challenges for a potential developer looking to practise their skills. This kind of entertainment has been a staple of computing and scientific magazines since the ’80s – my first exposure was ‘Computer Recreations’ (Scientific American) and that led to JJ Clessa (Leisure Lines – Personal Computer World magazine and his book “Math and Logic Puzzles for PC Enthusiasts” by JJ Clessa – ISBN: 9780486291925) and last but not least Martin Gardner (magazines and books). I appreciate the challenges of managing such…

Many traditional X11-based applications don’t work with the Mir display server that powers Unity 8, not out of the box anyway. For example, try opening Firefox or LibreOffice Writer and you’ll be met with a splash screen and spinning progress doodle that goes nowhere. These last-generation applications can be coerced into running using the Libertine sandboxing layer. This runs old packages safely inside an LXC container. One of the (many, many) reasons there is such a push to move away from X11 is because there is no inbuilt mechanism for isolating applications from one another. Any client can read input events and window data from any other, which makes writing keyloggers and other spyware much easier. This is a serious problem, especially when we consider that different users may be…

ON NORA THE EXPLORER “Nora is a little robot car, where video feed is sent to a virtual reality headset.” Lorraine is from Ireland and works with teachers in Lancashire to help them gain confidence in teaching computing. Lorraine is new to the maker community and this is her first Maker Faire UK, and she has chosen to show off her new project: Nora the Explorer, a first-person virtual reality robot. LXF: Hi Lorraine, can you tell the readers a little more about yourself? Lorraine Underwood: I’m the Computing at School coordinator for Lancaster University. Computing at School is a government funded organisation that helps teachers teach computing. Today at Maker Faire UK I am here with my project Nora the Explorer. LXF: So what is Nora the Explorer? LU:…

One of the oldest CPU benchmarks is the venerable LINPACK. This was originally written in the ’70s and is a collection of taxing Fortran programs for performing linear algebra – operations on vectors and matrices. This was written to test the supercomputers of the era, and it has now been mostly superseded by LAPACK, which makes better use of native vector operations and other voodoo in modern architectures. Nonetheless, LINPACK still remains vaguely relevant since a great deal of supercomputer time today is still spent inverting matrices. It’s not really a standard any more, there are several different versions you can get from www.netlib.org/benchmark. Netlib is a repository of mathematically themed papers and programs and well worth investigating if you’re of a scientific programming bent. The most modern LINPACK implementation…

Our expert Les Pounder Les works with the Raspberry Pi Foundation as part of their Picademy training, and travels the UK helping schools and teachers do more with tech. He blogs at http://bigl.es All models of Raspberry Pi come with the GPIO, the pins that enable the use of electronic components and add-on boards. But no model of Raspberry Pi can interact with analogue components, as the Pi does not come with an Analogue to Digital Converter (ADC). Step forward the MCP3008 ADC. In this tutorial we shall use it with three potentiometers to control a neopixel ring. Hardware setup Please refer to the wiring diagram (see You Will Need, below) for this tutorial, there are quite a few connections to be made. We start the hardware build by inserting…

There’s no shortage of suitable small monitors to connect to your Pi. If you feel comfortable with a small amount of wiring, the Official Raspberry Pi 7-inch Touchscreen Display is the ideal size to display a calendar, as well as having a handy slot at the back to place your Pi. The screen, along with assembly instructions, is available from the Pi Hut website for £55 (https://thepihut.com). If you don’t like messy wires, the Pi Hut also sells a short micro USB power cable for £2 to allow the Pi to draw power from the monitor’s USB port. The Raspberry Pi Touchscreen Display has the added advantage of enabling you to scroll through appointments with a click of a finger. If this is not important to you, or the display…

If you’ve enjoyed this small taste of the Learn Linux in Five Days Udemy course, you can gain unrestricted access to the full course at udemy.com with this exclusive Linux Format reader discount. You’ll discover a full working knowledge of using the standard sysadmin terminal tools, setting up a test machine, Linux file permissions, standard text editors, manipulating files, using network transfers, controlling processes and much more. Get the discount, start learning! Visit www.bit.ly/LearnLinux5 to enroll in the course at a discounted price of £15* (92% off)! Click the Buy Now button and sign up for an account on Udemy. Once you have signed up for an account, you will be asked to confirm your purchase. The discounted course price of £15 will be applied automatically with the above provided…

All terminal profiles are managed by the dconf tool, which is a low-level tool for managing various configuration and system settings. You can use dconfto read the values of any settings (referred to as keys) that you’ve previously configured using the Profile Preferences dialog box. First, make a note of the Profile ID of your chosen profile as found under the General tab of its Profile Preferences dialogue box. Once identified, return to the command line and type the following, substituting your exact Profile ID (including the leading colon character) for <profileID>: $ dconf list /org/gnome/terminal/legacy/profiles:/<profileID>/ Only those keys you’ve already configured will appear. To view a specific key’s current value, use dconf read like so: $ dconf read /org/gnome/terminal/legacy/profiles:/<profileID>/exit-action Substitute exit-action with your chosen key. You can then use…

You may get stuck at some points in setting up your pfSense system. That’s normal, after all this is not the complete exhaustive guide on everything to do with pfSense. Luckily, there are many resources online to help you in your journey. Since pfSense is such a popular and well-known router/firewall operating system, it is very easy to find detailed documentation and troubleshooting tips for almost every single problem you may run into. One recommended tool to use is the official documentation for pfSense at https://doc.pfsense.org/index.php/Main_Page. The documentation provided by the developers is quite detailed and thorough, providing many troubleshooting tips for the most common issues. The documentation covers installation, features, release versions, FAQs, packages to expand pfSense’s capabilities, and of course, a section devoted to troubleshooting. In addition, the…

Nginx is not just a web server; it can do many other tasks equally well including some of the tasks that can be performed by HAProxy. The main advantage of Nginx over HAProxy is the integration that it offers, which also means that you will have to learn just one piece of software to do your job. On the other hand, this is also a disadvantage because everything you do depends on a single piece of software. Additionally, most of the time specialised software tends to perform better than relatively generic tools, has less bugs because it has a smaller implementation and performs faster because it has a simpler design. Of course, the integration Nginx offers allows you to perform routing based on information found in the HTTP layer, which…

An OpenPGP certificate contains a public key, one or more user identities and one or more public subkeys. However, certificates are commonly but mistakenly referred to as keys, like the key servers that really serve certificates. The correct terms are described in RFC4880 and in the PGP book An Introduction to Cryptography which you can find at (http://bit.ly/2n6Lwmgf). This misrepresentation is also discussed at http://bit.ly/2nzn7RD. For this tutorial we’ve kept with common parlance and used “key” throughout the text.…

Now that you have a finished router, you may be itching to go even further. There are limitless possibilities for what to do now. The interesting thing about building your own router is that you are now in charge of both your hardware and software, and you will have resources to spare to add functionality such as ad-blocking software, and have it all in one box. If you wish to add extra functionality, there are many tutorials on the internet to help you on your journey. You can also work on adding new hardware, such as network expansion cards, additional storage and RAM, even adding additional operating systems and programs to make a multifunctional server system. You can purchase wireless access points and network switches to connect all your wired…

The example code (shown above) demonstrates how easy Django makes it to develop applications. With less than 30 lines of view code, you’re able to take care of listing news articles, creating new articles, viewing them, updating them and deleting them. This is made possible to the amount of time spent by the Django developers in creating a collection of generic views which are both useful, but also unopinionated. They deliver all of the functionality you require without getting in your way – and if you don’t like the way they’re doing something, you can just override or extend them with your methods. This level of thinking extends across the entire spectrum of Django features, with simplicity and security being the default. Knowing that the framework is doing all of…

Installing Vim is a good choice if you plan to access remote servers or need to make quick changes with the command line. On top of that, it is a fantastic editor and one you can use for changing files with super user privileges. A few such files where you need super privileges are php.ini and /etc/apache2/ apache2.conf and /etc/php/7.0/apache2/php.ini. apt-get install vim If you don’t want to use Vim to alter files, you can use Nanowhich ships with Linux. But if you spend some time with Vim, you may find its navigation and saving a real asset. It won’t save the file until you command it to do so. Here is a little list of simple Vim commands, most are preceded by <escape>. G – moves you to the…

One of the problems faced by commercial software is that of release dates. If you have geared up for a ridiculously extravagant marketing campaign starting on a particular date, you had better have brought your product to market, even if it’s not ready – you can always fix bugs later (Service Pack can be translated as “what marketing didn’t give us time to do properly"). Open source software often prides itself on its “release when it’s ready” approach, even though this often results in frustrating delays. Debian’s slow and arduous testing process may mean we wait ages for the next release and it is out of date by the time it arrives, but you can bet your job on it being stable, as many sysadmins do. However, Ubuntu shows us…