Linux FormatDecember 2016的目錄

Jonni Bidwell Bashcompletion is easy to overlook and hard to live without. A cheap Virtual Private Server (VPS) running Nextcloudis easy to maintain and much cooler than big-name alternatives. And a semi-transparent drop- down terminal will make you the envy of your co-workers. Nick Peers I’ve just treated myself to a QNAP TS-251+ network drive, with quad-core Celeron processor and 8GB RAM. Not only has my media server been given a shot in the arm, but it’s capable of running Docker applications and even full-blown Linux VMs. Exploring these features is going to be fun! Les Pounder A change of window manager is the ultimate turbo boost for Linux. Swapping out the bloat for something leaner will enable your computer to speed through tasks. I particularly like Openbox as it…

“Why are you in open source? Because of the money? For the prestige? Because there are lot of perks? Most of us in the open source community have slightly different priorities. The fact that open source allows us to work on interesting projects, for instance. Or that we’re dealing with cutting-edge technology. Those, in any case, were the two top answers given by the open source professionals we surveyed for our 2016 Open Source Jobs report. Only a tiny minority (2%) cited money and perks as the best part of their job. Open source is a special place to be. That’s what Jim Zemlin emphasised in his keynote speech at this year’s LinuxCon in Berlin. The Executive Director of the Linux Foundation spoke with great enthusiasm about what has made…

Nice to see the article about the PirateBox in the recent LXF [Tutorials, p62, LXF214] as it meant for once I would be ahead of the game. Every month I buy LXF, and every month I look at the projects thinking “That would be cool to do…” and then a mere month later, before I’ve had the chance to carry out the project, you buggers have brought out another issue and so the cycle repeats. Well, I have been using a PirateBox since the RasPi first came out, with one of the original batch no less, to serve up mark schemes and worked solutions, both written and video, to the students in my GCSE and A level maths class on their mobile phones. More recently I have been using the…

Chromebooks are renowned for their long battery life but with new Chromebooks having larger, higher resolution displays and more demanding components, battery life is bound to suffer. The Toshiba Chromebook 2 only lasted 6 hours and 2 minutes between switching through a dozen Chrome tabs, streaming Google Music, slipping into an hour of YouTube and writing this review. Compared to the original Toshiba Chromebook, the extra power draw of the Core i3 processor shortened battery life by 24 minutes. Meanwhile, HP claims the 14’s 3-cell, 37-watt-hour battery can last over 8 hours on a single charge. For us, it managed 5 hours, 38 minutes when playing an HD video file in VLCon loop (50% screen brightness, 50% volume with headphones plugged in). Intel promised better battery life with Broadwell processors,…

“Think of the stock release as a dev kit that can be moulded according to your wishes.” The well-oiled Ubuntu team has put out yet another Ubuntu release. Ubuntu 16.10, codenamed Yakkety Yak, is chiefly made up of incremental changes. The developers are focused on the next iteration of the underlying core components that will pave way for the distribution’s (distro) move to multiple devices. While you can’t argue against Ubuntu’s rock solid underpinnings, the distro as a whole isn’t as suave as it was in its early days—it has lost some of its lustre in its quest for stability. Ubuntu is perhaps one of very few distros that are both loved and loathed in equal measure. While you can’t deny it brings in new users; it’s also guilty of…

In addition to taking corrective action, Ubuntu can help you detect early signs of common hardware failures, such as dying disks and faulty RAM. Virtually all hard disks these days ship with the SMART status system that allows a failing hard drive to warn you before it goes down in flames and takes your valuable data along with it. To check a drive’s SMART status from Ubuntu, launch the Disks utility from the Dash. Select the drive you wish to check and click the three parallel lines to bring up the menu of options. Select the ‘SMART Data & Self-Tests’ option which brings up a window with details about the disk and an option to perform a self-test. While the tool isn’t perfect, if it reports an error with one…

It’s an obvious point with older systems, but 32-bit systems are slower than modern hardware, but that’s not down to the CPU alone. Older computers often have less (and slower) system memory and nothing boosts the performance of Linux than plenty of elbow room in the RAM department. The x86 architecture is limited to addressing 4GB of memory and many systems allow access to less with the default BIOS settings. This is why things like a lighter desktop can make so much difference. There is a way to beat the RAM limit and this is called PAE (Physical Address Extension) and some distros offer a choice of PAE and non-PAE versions. If your processor supports it (PAE was introduced with Intel’s Pentium Pro processors) and you have or are likely…

You will see lots of terms used to describe processor families, so many that it becomes confusing. The 386 was the first 32-bit processor family from Intel, so anything labelled i386 will work everywhere. The 586 was the Pentium with the 686 being the Pentium II. Some distros label their packages as i586 or i686, you would have to have a very old computer to not be able to use these. The entire 32-bit range is also known by the generic term of x86, while 64-bit processors are either amd64 or x86_64. These are the same, even Intel 64-bit CPUs use amd64 software, because AMD invented the standard—in the same way that i386 code also runs on AMD 32-bit hardware.…

OnlyOffice DE SVG Cleaner GUI KolorManager Ungoogled-Chromium Profile-sync-daemon Kexi Vim Gradio Feh Dave Gnukem Quetoo “OnlyOffice works natively with Microsoft OOXML (DOCX, XLSX).” Office suite OnlyOffice DEs Version: 4.1.2 Web: http://bit.ly/OnlyOffice Will 2017 be the year of Linux on the Desktop? Yes, that joke never gets old. However, It does look like something tectonic is happening beneath the software world or at the very least there’s more good news for those who run productivity applications on Linux. One of the ever-present obstacles for Linux has always been the compatibility with Microsoft Office file formats, specifically the ability to open incoming DOCX or XLSX files, edit and save them for other people without breaking formatting or suffering from visual inconsistencies across platforms and applications. Despite the fact that LibreOffice is very…

The simplest way to control Mopidyis through your web browser. And the good news is, not only is there a rich choice of front-ends to work with, you can install multiple ones side by side and switch between them through the main Mopidyweb page (http://hostname.local:6680/mopidy). If you want a slicker, albeit more minimalist alternative to the MusicBox Webclient interface, we recommend installing Mopidy-Moped You can also add a Settings option with Once installed, you’ll see the option appear on the main Mopidy page and from here you gain easy access to configuring various online streams, including Spotify (Premium only), Google Music and SoundCloud. Finally, the Mopidy-Mobile front-end has one killer feature the other front-ends lack: the ability to create and manage playlists from within your web browser.…

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. Terminal Control your Android device remotely using Android Debug Bridge When your Android phone or tablet goes wrong, what can you do to fix the problem? Perhaps its touchscreen is playing up, or it’s too unstable to browse, or maybe there’s data that you desperately need to get off it. In all of these circumstances, your trusty PC can come to the rescue, courtesy of the Terminal and a set of tools called adb(Android Debug Bridge), which enable you to connect to your device and control it through your shell. The bridge consists of three components: client, server and daemon. Both client and…

Our expert Mayank Sharma has many secrets on his hidden drive. If only he could remember the password so he could open it. VeraCrypt Create an encrypted disk and hide volumes within volumes A simple user password is not enough protection for your critical data and personal files. To truly protect your files from being routinely accessed, manipulated or disappeared as some miscreants are wont to do, you must encrypt your data. If done right, encrypted data appears unintelligible to people without the means to decrypt it. The most basic option to protect yourself is to individually encrypt each of your sensitive files. But this a time-consuming and tedious process and requires routine decryption of such files which is a further waste of time. The smarter way is to create…

Instead of local logins, some people prefer to enable two-factor authentication only for remote SSH logins. For this, begin by making sure you’ve generated a code for the user you want to log in as the remote user. Next, make sure you use Google Authenticator for SSH logins by editing SSH’s PAM configuration file with sudo nano /etc/pam.d/sshd . Scroll down to the bottom and add the following line to the file: Just as in the main tutorial, the nullok word at the end tells PAM that this authentication method is optional. This allows users without a Google authenticator key to still log in using their SSH key. Remember that this is just a failsafe to prevent you from being locked out in case something goes wrong with the setup…

Our expert Mihalis Tsoukalos (@mactsouk) has an M.Sc. in IT from UCL and a B.Sc. in Mathematics, which makes him a DB-admining, software-coding, Unix-using, mathematical machine. You can reach him at www.mtsoukalos.eu. Wireshark Wi xxx eshark Analyse network traffic using Wireshark and tshark Wireshark, as well as tsharkwhich is the command-line version of Wireshark, are the best tools for analysing network traffic of almost any kind. This tutorial will show you how to use tshark, including using it with Perl and Python; cover its Flow Graph feature and traffic statistics. We’ll also present a real scenario that involves the DHCP protocol and how to solve it using Wireshark. If you don’t have Wiresharkand tsharkalready installed, you can install both of them on Ubuntu as follows: At the time of writing,…

Our expert Mihalis Tsoukalos (@mactsouk) has an M.Sc. in IT from UCL and a B.Sc. in Mathematics, which makes him a DB-admining, software-coding, Unix-using, mathematical machine. You can reach him at www.mtsoukalos.eu. This tutorial will continue from where we left off last month. You are going to learn more statistical learning techniques that can be applied to real data taken from the log files of a website served by Apache. We’ll present examples in two methods while briefly talking about some other handy techniques that you need to know. The two techniques that you’ll learn to use are Markov Chains – where a Python script will be presented – and Linear Regression. Both of these techniques are simple enough and can be easily used to process your own data. After…

Our expert Kent Elchuk has worked for many years as a full-time web developer and technical writer. He is currently the owner of Fullstack Web Studio. This tutorial will dive into the usage of the JavaScript library called jQuery and Angular.js, a JavaScript framework. Both tools are very popular for building anything from simple websites to elaborate website applications to mobile apps. Since SPA (Single Page Applications) are very popular these days, there will be an emphasis on how to create them with custom JavaScript. By the end of the article, you’ll understand how to set up, build and test a basic web application using both of these JavaScript resources. In addition, you will have some insight as to when to use either of the two options. Before we get…

1 Migration questions Q I have been dabbling with Linux for years, but there has always been a deal breaker with regards to using it full time. But as both a Mac and Windows user I have become very unhappy with the path that both companies seem to be taking so it was time for me to try harder. I installed Mint 18 (64-bit) on a 13-inch MacBook Pro 9.2 with very few problems. One that causes some concern is how hot it gets when playing AV content. Most articles I have read about Linux on Macs they always seem to use old hardware—do you have any idea what the newest kit would work? I’d really like to use a more powerful Mac mini attached to a large monitor or…

★ Windows with Mint Q I have been using Mint 17.3 on a desktop PC for some time. I recently bought a new Lenovo G50 laptop with Windows 10. I want to add Mint 18. I tried to run the Live version straight from the LXF214 DVD but it wasn’t recognised at boot up, so I tried using a USB stick. I used the application on Mint 17.3 to load the linuxmint18-cinnamon-64bit.iso file from the DVD onto it. It didn’t work. I changed the BIOS setting on the Lenovo to allow Legacy booting and this time I was able to run the Live Mint 18 boot. When I went to Install I got an error message about a Boot recovery partition. Checking the message on the web, I found an…

We have two distros   with distinct appearances on this month’s DVD. Ubuntu and BunsenLabs look and feel very different to use, but they are both Linux. More than that, they are both based on Debian; they are both first-gen respins if you like. One is produced by a company and the other by a community of users, but both do what they are intended to do very well. Try explaining that to a Windows or Apple user and they will probably stare at you blankly. They are so used to getting what they are given that the idea of being able to pick and choose core elements of the OS is something they’ve not even considered. The open source nature of Linux makes this activity not only relatively easy…

While us Northern hemisphere types pull out the thermal underwear to endure chillier weather and longer nights, we do get the bonus at this time of the year of a whole new Ubuntu distro release to enjoy. Ubuntu 16.10 has hit the internets and brings with it a host of updates, upgrades and Ubuntus. This issue we’re not going to dwell on the core release – where enhanced support with the Linux kernel 4.8 and the Unity 8 preview are the highlights – instead we’re asking how can you make Ubuntu even better? Install Fedora you cry? Surely not, though Fedora 25 is just around the corner. Our resident experts have given us their tips on how to boost Ubuntu and make it even better. Talking of winter, in some…

BODHI LINUX 4.0.0 Bodhi Linux 4.0.0 has now been released and is based on Ubuntu 16.04, which as you’re probably aware is an LTS release supported up to April 2021. It comes with a custom Moksha desktop environment (based on Enlightenment), which has recently been updated to 0.2.1. The Linux 4.4 kernel and EFL 1.18.1 are included, and it’s available in both 32-bit and 64-bit. An AppPack version comes with core programs preinstalled, while the Legacy version is designed for older computer. To download head to www.bodhilinux.com/download. MAUI LINUX 2 Anew version of Maui Linux has been released, and it is now based on the KDE neon project. The move is so the project developers have more control over when to push updates to users while also giving them the…

Find and join a LUG Blackpool Makerspace 64 Tyldesley Road, Blackpool 10am every Saturday. https://blackpoolmakerspace.wordpress.com Bristol and Bath LUG Meet on the fourth Saturday of each month at the Knights Templar (near Temple Meads Station) at 12:30pm until 4pm. www.bristol.lug.org.uk Tyneside LUG Meet from 12pm, first Saturday of the month at the Discovery Museum, Blandford Square, Newcastle. www.tyneside.lug.org.uk Liverpool LUG Meet on the first Wednesday of the month from 7pm onwards at DoES Liverpool, Gostins Building, Hanover Street , Liverpool. http://liv.lug.org.uk/wiki Lincoln LUG Meet on the third Wednesday of the month at 7:00pm, Lincoln Bowl, Washingborough Road, Lincoln, LN4 1EF. http://www.lincoln.lug.org.uk/ Surrey & Hampshire Hackspace Meet weekly each Thursday from 6:00pm at The Boiler Room in Guildford. www.shmakerspace.org Egham Raspberry Jam Meet at Gartner UK HQ every quarter. http://winkleink.blogspot.com Manchester…

Although the Chromebooks in this Roundup are geared to more lifestyle applications, we want to see good essentials, such as the keyboard and trackpad. For the Toshiba Chromebook 2, the keyboard is more than serviceable with a traditional layout and the backlit keys—a rare feature for Chrome OS devices. Just below the keyboard, the trackpad is sizable and clicks with precision. We were pleasantly surprised by the typing experience on the HP 14. The keyboard feels responsive with clicky keys and plenty of key travel. However, there’s no dedicated Caps Lock key; a Search key. The trackpad is equally excellent. It’s big and spacious and the whole trackpad is a button. The large size of the Acer 15 means there’s plenty of room for a full-size keyboard. There’s also a…

While there is consensus in the community to phase out the ageing X windows system, the community is divided on its replacement. Most Linux distros are moving to Waylandwhile Ubuntu has once again decided to go its own way by creating its own graphics server called Mir. However, both Waylandand Mirare still under active development and most stable distros, including Ubuntu 16.10, still continue using X. At the moment, Mir is expected to be the default display server in Ubuntu 17.04. Keep in mind, however, that Mir’s release has been pushed back in every release since 13.10, so we’ll keep the champagne on ice until Mir shows up in the release note. You can try both Mirand Waylandon top of Ubuntu. Mirand Unity 8, the next major iteration of the…

Once you’ve loaded the right drivers in your Ubuntu install, it’s time to pay a visit to the repos and stock it with the best multimedia applications. For gaming buffs, besides the various open source titles, there’s the Steam game distribution platform. The number of AAA titles available on Steam for Linux continues to rise and you can expect more as the gaming platform aligns behind Linux that powers their Steam OS and the upcoming gaming consoles. For video conferencing, there’s no better option than Jitsi, as long as you’re not adverse to Java apps. It also supports popular instant messaging protocols and can make one-to-one and conference audio and video calls. Jitsi has all the features you’d expect from a softphone, and more, such as encrypted text chats with…

Dan Cauchy is General Manager of Automotive at the Linux Foundation. He’s in charge of Automotive Grade Linux (AGL), a project that aims to provide a single platform around which auto makers can build systems for In-Vehicle Infotainment (IVI), instrument clusters and, probably one day, replace meatbag drivers. No stranger to embedded Linux, he’s previously worked for Montavista and was a board member for the GENIVI alliance. He’s originally from Canada and is a keen hockey player. Linux Format: Tell us about AGL, why does it exist? Why don’t car manufacturers roll their own automotive software? Dan Cauchy: Automotive Grade Linux is a nonprofit open source collaborative project hosted by The Linux Foundation. The reason AGL exists is because car manufacturers have basically fallen behind the smartphone in terms of…

At this point you may be thinking any 32-bit computers must be really old now, why not simply replace them? That’s a fair point in some circumstances, but the old axiom of ‘if it ain’t broke, don’t fix it’ still applies here. A 32-bit computer won’t make much of a gaming rig (unless you are into retro games) but it is more than up to common desktop tasks such as email, word processing and basic web use—you don’t need many GHz to update your Facebook status. Even if you no longer have a use for your old hardware, you could donate it to someone who does, whether that’s a family member or a local community centre. Many Linux User Groups (LUGs) often maintain some very old hardware that’s more than…

Distracted much? Lately, I’ve got back into the habit of listening to audiobooks of late (I recommend listening to them at a slightly faster speed than the default). On recent commutes I’ve been absorbing Deep Work by Cal Newport which has given me much to think about. In it, Newport discusses developing the ability to focus without distraction on cognitively demanding tasks. This deep work of the title is contrasted with what the author categorises as shallow work—email, group chat, meetings, social media and such like. I groaned inwardly as I realised how closely my day-to-day work habits matched the distracted state being described to me via my headphones. I often find that large tasks are a struggle to complete, I read online news and articles voraciously and my social…

InfraKit has garnered some attention thanks to being announced by Docker, which remains the headline name in the container market (despite recent rumours of forks and grumbling in the open source community). But InfraKit has landed in a very competitive niche. As well as the familiar configuration management names (Puppet, Ansible and Chef et al) there are alternatives such as Terraform (www.terraform.io —which InfraKit provides a plugin for, of course), Bosh (https://bosh.  cloudfoundry.org), Rancher (http://rancher.com which I’ve covered in the past), Mesos (https://mesosphere.com), Packer (www.packer.io), Kubernetes (http://kubernetes.io) and Spinnaker (www.spinnaker.io). All of these products and projects cover elements of what InfraKit is trying to achieve. This is the nature of open source and should be celebrated, but sysadmins can be forgiven for getting a slight headache when considering which options…

Raspbian has been with us since the very early days of the Raspberry Pi. Initially, the default operating system was to be a version of Fedora but just at the last minute the Raspbian project pipped them to the top spot. Raspbian was a functional, if unremarkable desktop experience. It uses the LXDE window manager to squeeze as much power from the early Raspberry Pi’s meagre resources. But under the stewardship of Simon Long, what was once an ugly duckling has now grown into a rather beautiful swan. The latest version of the Raspbian desktop, code named Pixel, was released on September 29 and caused quite a stir. Pixel now provides the same desktop experience that we expect from modern OSes. Pixel also introduces a more refined way to control…

Converting text to speech is rather tricky, even for a computer like the Raspberry Pi which has a multi-core CPU that can power through common tasks. Converting text to speech needs a special API (Application Programming Interface) that can work with another service to provide the necessary power. Step forward gtts , short for Google Text To Speech, which is a Python interface to this service provided by Google. When you first run gtts, you will hear the familiar voice that is present on many Android applications, but did you know that you can also change the accent of the voice? Remember that we used this piece of code in our tutorial: Well we can change the language, identified via so that we have a different accent. Try…

1 Open network config file Reconnect your card reader, then type again to see the mount point of the larger (1.2GB) partition, something like /media/nick/3598ef8e… Now change to that directory and then open the network configuration file (note there’s no before the directory): 2 Tweak Wi-Fi settings Locate the line beginning with and add the following line above it: Change the line: to the following: Save and exit nano (Ctrl+x), then type: 3 Add Wi-Fi credentials Finally, you will need to add the following lines to the end of the configuration file, making the appropriate changes to and then save and exit:…

It’s possible to remotely access your Android device over Wi-Fi, so long as your PC and device are both on the same local network (Ethernet or Wi-Fi). The first time you set this up, you’ll need to connect your device to your PC via USB, then type the following: You’ll be told that adb is restarting. Now unplug your Android device from your PC and type the following: Replace 192.168.x.y with your Android device’s IP address (get this from Settings > About tablet > Status > IP address). You should see a message saying, connected to 192.168.x.y:5555 indicating you’re good to go. If the connection drops or you’re attempting to connect after rebooting your PC, type: Again—if it fails, simply repeat the command, and in most cases you’ll reconnect. But…

The standard volume header uses the first 512 bytes of the VeraCryptcontainer. It contains the master keys needed to decrypt the volume. If the header gets corrupted, VeraCryptwill no longer be able to mount a volume. To prevent such an occurrence, each volume created by VeraCrypt also contains an embedded backup header, located at the end of the volume. But just to be doubly sure that no travesty befalls the guardian of all your secrets, you can create an external backup for the headers. From the main VeraCryptwindow, select the volume file and then click Tools > Backup Volume Header and follow the instructions on the wizard. If your volume also contains a hidden volume, the wizard will ask you for its password so that its header info is also…

Our expert Arthur Baxter is a Network Operations Analyst at ExpressVPN, a leading privacy advocate whose core mission is to make it easy for everyone to use the internet with security, privacy, and freedom. VPN Xxxx Get started with a virtual private network using the CLI The internet was supposed to be open and permissionless, transcend borders and make the world a smaller place. Some of that has been achieved, but there is also a creeping feeling that ISPs (Internet Service Providers), nation states, and web services are increasingly locking down their networks, imposing censorship and discriminating based on computer, browser, and IP address. Many technologies aim to free information from censorship and geo-restrictions. Most restrictions are only placed on the internet artificially and superficially, and can easily be circumvented.…

Although Wiresharkis a great and powerful application to use, there are times that you need something lighter for your work, and something that can execute remotely without a graphical user interface. In such situations, you can use tshark. The following Perl script, for example, shows how to use tsharkto automate things: If you attempted to do the same thing using the graphical interface of Wireshark, it would take more time and system resources and cannot be executed as a cronjob. Additionally, you can easily process the output of tsharkusing traditional Unix command line tools, such as grep, AWK and sed, etc. Nevertheless, when you want to look closely at the contents of lots of network packets, using Wiresharkinstead of tsharkis almost mandatory because the graphical interface makes your life a…

Function This is a relation between a set of inputs and a set of possible outputs where each input generates a single output. Probability an area of mathematics that is related to statistics and deals with the measurement of the likelihood that an event will occur. The distribution of a variable is a description of the relative numbers of times each possible outcome will occur in a number of trials. Algebra A very popular area of mathematics that deals with mathematical symbols and the rules that can manipulate these symbols. Relational algebra is the foundation of database theory because it deals with the modelling of the data stored in relational databases. The other important areas of mathematics are number theory, geometry and analysis. Statistics An area of mathematics that deals…

Building single-page applications with the front-end Bootstrap framework makes it easy to build one site for all devices. To put a name to it, this is called responsive design. The basics of responsive design involves the use of CSS classes and you build a page from the top down in sets. From a coding point of view, when you create a <div> element with the class ‘row’, you have made one set. You can have as many rows as you want and even place rows within rows when necessary. Within the rows, you will have columns. By default, you build the columns using class names too. Thus, you may have three columns with the same class ‘colmd-4’. The key to using columns is that they must add up to 12,…

Linux Format is proud to produce the biggest and best magazine that we can. A rough word count of LXF193 showed it had 55,242 words. That’s a few thousand more than Animal Farm and Kafka’s The Metamorphosis combined, but with way more Linux, coding and free software (but hopefully less bugs). That’s as much as the competition, and as for the best, well… that’s a subjective claim, but we do sell way more copies than any other Linux mag in the UK. As we like giving things to our readers, each issue the Star Question will win a copy or two of our amazing Guru Guides or Made Simple books – discover the full range at: http://bit.ly/LXFspecials. For a chance to win, email a question to lxf.answers@futurenet.com, or post it…

While installing Linux on a new computer, I was given the option to use LVM—what is that? This is the Logical Volume Manager, which uses logical volumes to hold your filesystems instead of disk partitions. How does that work? Each disk or partition you want to use is set up as a Physical Volume (PV). Then one or more PVs are combined to create a Volume Group (VG). A VG you can create logical volumes on it that operate just like traditional disk partitions. That sounds awfully complex and what’s the point? Because you have more than one PV in a volume group, it’s easy to add disk space and almost as easy to remove it, when you need to do that. Fine, but I only have one disk, is…

System tools Essentials Checkinstall Install tarballs with your package manager. Coreutils The basic utilities that should exist on every operating system. HardInfo A system benchmarking tool. Kernel Source code for the latest stable kernel release, should you need it. Memtest86+ Check for faulty memory. Plop A simple manager for booting OSes, from CD, DVD and USB. RawWrite Create boot floppy disks under MS-DOS in Windows. Smart Boot Manager An OS-agnostic manager with an easy-to-use interface. WvDial Connect with a dial-up modem. Reading matter Bookshelf Advanced Bash-Scripting Guide Go further with shell scripting. Bash Guide for Beginners Get to grips with Bash scripting. Bourne Shell Scripting Guide Get started with shell scripting. The Cathedral and the Bazaar Eric S Raymond’s classic text explaining the advantages of open development. The Debian Administrator’s…

How to… Get into Linux Get you, get your friends, get your loved ones and get your work into Linux, we explore how it’s for everyone! Build the fastest Linux PC We’ve asked sister magazine Maximum PC to build us the fastest Linux PC ever—at a sensible price point. Wayland revolution Finally make the leap from the ancient X11 graphics to the all singing, shiny Wayland system, the easy way… You lightweights If you have the slowest Linux PC in the world, we test the lowest resource distros that can help it run faster.…

“Torvalds admitted that he’d attempted to fix the problem 11 years ago.” A bug found in the copy-on-write feature of the Linux kernel (hence the COW in the name) has been exploited, so that it can allow installed applications or malicious code, to access root and hijack the device running Linux. The security lapse allows code to change what should be a read-only root executable stored in memory. This enables potentially malicious code to be committed to storage, essentially allowing programs with standard user privileges to alter root-owned files and executables. Perhaps most worryingly, this vulnerability has been in the Linux kernel since 2007’s 2.6.22 version. According to The Register, the flaw is also present in Android, which dramatically increases the number of potentially vulnerable devices. The flaw hadn’t gone…

It’s that time of the year again where speculation grows over what alphabetically-themed animal codename the next version of Ubuntu will have. To put your minds at ease, Canonical head honcho Mark Shuttleworth has revealed on his personal blog that Ubuntu 17.04 will be known as Zesty Zapus—named after a jumping mouse from North America. So why that name? Shuttleworth sees Canonical as a tiny, yet plucky, mouse amidst a market of giants, which can easily jump over “the obstacles of life”. With that important consideration out of the way we can look forward to news about what new features 17.04 will bring. If you’re still clinging on to your Yahoo email account, then the latest news might make you consider ditching the creaking email account, as it appears Yahoo…

3D photo It’s great to see more information on 3D printing and your latest article (Roundup, p24, LXF215) is to your usual high and comprehensive standards, but would it be too much to ask to see images of printed items? It’s the usual story that a picture paints a thousand words and seeing finished items would greatly enhance articles such as these. I Hope you can show some next time. Ian Hartas, via email, Neil says: I’m glad you liked the Roundup, it’s good to know there’s interest out there on the subject! We’re lucky that Ali Jennings has the time to review them for us, as he’s pretty busy, but has used them extensively. It’s a good point about an image of the output, it’s something that hadn’t occurred…

In this Roundup, we mainly looked at Chromebooks that push the envelope of what we expect from these devices. This means we focused on Chromebooks with some of the latest technology, impressive screens and powerful components. However, there are still a lot of Chromebooks that focus on what made these devices so popular in the first place—low prices and dependable but not flashy performance. For example, the Acer Chromebook 13 concentrates on being lightweight but with a fantastic battery life, making it ideal for students. The Lenovo N20p Chromebook is showing its age, but it’s a gorgeously designed Chromebook that’s very affordable. Meanwhile, aside from the budget price tag, the Asus Chromebook Flip is one of the best-built Chromebooks to blaze the trail onward for more laptop/tablet convertibles. Touchscreen functionality…

Ubuntu has often been criticised by privacy and security advocates. For instance, it used to be that anything you entered in the Dash returned results from etailers, such as Amazon. This feature of Shopping Lens has been disabled by default now. But there are several things you can do to make your install more secure. You can selectively exclude some services from the results, bring up Dash and expand the Filter Results option on the right. Now deselect the categories or sources that you want to exclude from the search results. To disable the feature for good, head to System Settings and under the Personal section select ‘Security & Privacy’. Also, Dash displays all recently accessed files along with other files found on your system. If you happen to share…

You can use Ubuntu on a computer that lacks a dedicated graphics card, a multi-core processor or is underpowered in other ways. The biggest drain of resources on a distro is, you guessed it, the desktop environment. LXDE has been producing a functional lightweight desktop since before the dawn of flashy bling-laden desktops. The desktop is popularly used by mainstream distros to offer a variant of the main distro that’s less demanding on a system’s resources. Lubuntu is a good example of such a distro and enables you to reap the benefits of Ubuntu on a machine with just 128MB of RAM. LXDE shares the same basic layout as Cinnamon. While it’s not particularly attractive, it’s fully functional and helps keep the desktop clutter to a minimum and leaves enough…

MediaTomb ships with adequate defaults that’ll work for virtually all kinds of users. However, the streaming server is highly configurable. To make changes to its configuration you’ll need to edit the ~/.mediatomb/config.xml file in a text editor. The config file has two types of settings. The server will fail to load if one or more of the settings or tags marked ‘Required’ is missing, while on the other hand you can safely skip over the options marked ‘Optional’. The settings in the file are divided into several categories. The category controls various parameters that affect the server, such as the port, IP and network interface. There are also several optional parameters for controlling the web interface and can be used for locking access to defined user accounts. Then there’s the…

Along standing race condition in the Linux kernel’s memory subsystem related to how it handles certain copy-on-write operations (the ‘COW’ that gave the vulnerability its name) was disclosed in October 2016. Referenced as CVE-2016-5195 by MITRE, the issue was labelled ‘Dirty COW’ and quickly had its own, Twitter account, website (https://dirtycow.ninja), online shop and professionally created logo which was picked up by major news outlets. According to the discoverer, security researcher Phil Oester, a website he manages was compromised and he was able to capture the exploit via rolling packet captures he maintains of all inbound HTTP traffic. Linus Torvalds, creator of the Linux kernel, commented on the resulting kernel patch that this was an “ancient bug” that had been fixed once over a decade ago, but which had subsequently…

It’s worth being aware of the different types of plugins InfraKitoffers and to understand exactly what they are (from the project GitHub page: “Technically, a Plugin is an HTTP server with a well-defined API, listening on a Unix socket.”). Currently, there are three different types available: Group, Instance and Flavor. Groups are exactly what we would expect: collections of identical or similar machines which can be controlled by InfraKitand InfraKit provides some controls over groups, such as creation, destruction, how large they should be, whether they should shrink or grow and triggering updates. Instances are members of groups, individual VMs for example (although they don’t have to be machines at all—they are defined by the plugin). They may be tagged to aid with computing the state of a cluster. While…

Our expert Nick Peers was desperate to get Mopidy 2.0 running on his Pi Zero, and now he’s made the switch he’s sworn never to go back to PiMusicBox—and neither will you. A Pi Zero is the perfect tool for the job if you’re looking for an audiophile-friendly music player. Back in LXF211 [Pi User, p62] we revealed how to combine a Pi Zero with the Pi-DAC Zero add-on and PiMusicBox distro to deliver gorgeous sounds through your home stereo. PiMusicBox is based on the superb Mopidymusic player, but it’s not been updated for 18 months and is starting to show its age: for example, there’s no direct support for the Pi Zero or the Pi 3, and it’s based on an early version of Mopidy. In this tutorial, we’re…

MPD provides an alternative means of communicating and controlling Mopidy remotely. It’s more flexible in that you can access Mopidythrough a desktop application or mobile app as well as the web. MPD is also required if you want to use Mopidyas a DLNA client. To enable MPD support in Mopidy, you’ll need to edit the Mopidyconfiguration file as outlined in the main text. Add the following lines to the bottom of the file, substituting with a password should you want to password-protect access: Save and exit, then restart the server Now open your MPD client app—see https://docs.mopidy.com/en/latest/clients/mpd for a full list (we recommend GMPC in Linux, MPDroid on Android and MPoD on iOS). Your Mopidyserver should be immediately detected, and you’ll be able to browse, play and queue up…

Typing adb shell will put you at the shell of your Android device. The Android OS is loosely based on Linux, but supports far fewer commands than your standard Linux shell. That said, the operating system also has some handy commands you won’t find in Linux too, for example am (Activity Manager), which can be used to end applications if they stop responding, among other things. Try the ‘gentle’ approach first: This kills all processes associated with an app that are safe to kill and which won’t interrupt the user experience. If that doesn’t work, you can go further: Shell commands can be entered here, or you can enter them directly from your own Terminal using adb shell <command> . This latter approach works best if you only want to…

In addition to using passwords to protect your encrypted volumes, VeraCryptalso offers the option of combining passwords with keyfiles, which will significantly bolster security. Just about any file on your machine can be used as a keyfile. VeraCryptwill not mount a volume, even on providing the correct password, if the user also doesn’t specify the keyfile. The content of a keyfile isn’t modifed so there’s no risk of damaging the data it contains. While you can use any file as a keyfile, only compressed files such as MP3, TAR and JPG are recommended. In case of mp3 files, make sure that tags such as artist name, title, etc. aren’t modified, once the file has been used as keyfile. You can specify multiple files as keyfiles and even generate keyfiles using…

Our expert Mayank Sharma is so sceptical that he has to verify his authenticity every time he wakes up in the morning. He’s also a veteran tech writer… or so he says. Security Xxxx Use Google Authenticator to set up two-factor authentication Locking access to your computer (and the data it holds) with just a password doesn’t cut the mustard any more in this age of multi-core processors and easy to use password cracking tools. If you’re really concerned about unauthorised access to your computer, you should definitely add an additional layer of authentication. One of the easiest mechanisms to implement such a two-step verification is the Google Authenticator service, which issues a time-based authentication token to supplement the existing password challenge. Once you’ve integrated the service with your Ubuntu…

An Internet Service Provider (ISP) might be required by their government to introduce censorship tools or limit access to certain platforms or sites. An ISP might also voluntarily add such restrictions, possibly in a poor understanding of information security, or to limit the services its users can enjoy for commercial or legal reasons. A Virtual Private Network (VPN) could also impose censorship, but they would not be able to get away with it for long. Switching your VPN provider is uncomplicated and fast, and as long as the user demands an open internet, even if only in principle, the VPN provider will be forced by market powers to provide it.…

We often say that using a command-line utility is generally the best tool for getting information about your Linux system and tshark is no exception in that regard. The following tsharkcommand lists the available network interfaces: $ tshark -D . The -w parameter followed by a filename will store the captured data into a file with the given filename whereas if you use the -c parameter it allows you to specify the number of packets you want to capture. The -r parameter followed by an existing filename will allow you to replay a previously captured data file on your screen. You can also specify Display filters with the help of the -Y option followed by the actual filter you want to use in quotes, for example: Should you wish to…

There are two main distribution categories: continuous distributions and discrete distributions, and they are based on the type of the variable they support. The most useful and famous distributions are normal, binomial, poisson, beta and chi-square. The normal distribution can be described using only two parameters: the mean of the distribution and the standard deviation. It’s a continuous probability distribution because it can take a continuous range of values—there are no gaps between values. Binomial is a discrete probability distribution that’s quite simple to understand. It can be described using two parameters and can be explained using an example. Imagine that you have a dice that you are going to roll 20 times and you want to find the probability of having the number 6 appear exactly 4 times. You…

Search engine optimisation is an important aspect of building a SPA (Single-Page Application). In the modern era, Google does support JavaScript and you can render your pages using Google Webmaster Tools to see how your application fetches and renders the page. More details about this can be found from the horse’s mouth at the Google Webmaster Central blog (http://bit.ly/UnderstandingWebPages). To see how well your website is rendered by Google, you’ll need to login to the Webmaster tools and select the domain. This will put you at the Dashboard and after that, you simply select Crawl > Fetch as Google > (Add the URL into the input box) > Click Fetch and Render. Now that you are in Webmaster tools, you may as well create an XML sitemap for the URLs…

Sometimes you may execute a shell command and find its behaviour does not quite match that of the man page. This is because most shells, like Bashand ZShell, have duplicates of a number of core commands built in. This is done for speed and efficiency as the command doesn’t have to be loaded from disk before it can be used, it is already loaded as part of the shell. You can find a list of built-in commands in the man page for your shell (Warning: the Bash man page is very long but the information is in there). So what do you do if you want to run the ‘full’ version of the command rather than the built in version? That’s easy, you just give the full path, say /usr/bin/command…