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Linux-natives blog: Linux and open source – technology and strategy

Build a small and cheap Linux workstation with Intel NUC

Are you looking  for a workstation that is easy-to-use, virtually maintenance free and incredibly cheap to run? Perhaps your Grandparents require want to connect with the rest of their family?  Maybe you require a simple Internet kiosk for a public space? Whatever your needs, a modern Linux distribution, combined with inexpensive hardware, can provide viable […]

Vim – The Ubiquitous Text Editor (… and your new best friend)

ubiquitous /juːˈbɪkwɪtəs/: present, appearing, or found everywhere Vim is one of the grand old text editors, and while it’s history begins long before many current computer scientists were born, it still has it’s place in the toolbox of 2020’s technology workers. It’s default settings might however be too simplified, and make the tool hard to use […]

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Pimp your bash with Liquid Prompt

Linux users, software developers and power users alike spend a lot of time in the command-line prompt. The default Bash shell that ships in most Linux distributions have stayed pretty much unchanged for years and years. We wanted to explore how to improve the every day command-line experience, and eventually came very fond of the […]

Improve your security with two-factor authentication

Two-factor authentication (or simply 2FA) is a way of authentication where a user must provide additional verification after username and password login. The form of verification can be a string of characters delivered via text message or generated with TOTP client. Two-factor authentication improves security because compromised username and password are not enough to get […]

Magic wormhole – easiest way to transfer a file across the Internet

Transferring files between two computers on the Internet is as old of a problem as the Internet itself, and surprisingly hard. Sending an attachment over e-mail involves all kind of hassles and does not work for big files. Having both the sending and receiving part sign up for Dropbox or a similar service, or setting […]

Align user IDs inside and outside Docker with subuser mapping

While Docker is quite handy in many ways, one inconvenient aspect is that if one mounts some host machine directory inside Docker, and the Docker image does something to those files as a non-root user, one will run into problems if the UID of the host machine user and the Docker image user do not […]

Partition like a pro with fdisk, sfdisk and cfdisk

Most Linux distributions ship the hard drive partition tool fdisk by default. Knowing how to use it is a good skill for every Linux system administrator since having to rescue a system that has disk issues is a very common task. If the admin is faced with a prompt in a rescue mode boot, often […]

How to create good SSH keys

A couple years back we wrote a guide on how to create good OpenPGP/GnuPG keys and now it is time to write a guide on SSH keys for much of the same reasons: SSH key algorithms have evolved in past years and the keys generated by the default OpenSSH settings a few years ago are […]

Ubuntu/Gnome on a tablet

Back in 2012 we blogged about Meego/Mer/Nemo, Android for x86 and other Linux operating systems for touchscreens and tablets. Back in the day we also compared Ubuntu Unity vs. Gnome 3 and which would work better as a touch operated system, and Gnome 3 was clearly the more mature system. Since then Ubuntu has dropped Unity […]

Secure and flexible backup server with dm-crypt and btrfs

In our previous article we described an idea setup for a modern server with btrfs for flexibility and redundancy. In this article we describe another kind of setup that is ideal only for a backup server. For a backup server redundancy and high availability are not important, but instead maximal disk space capacity and the […]

The perfect Btrfs setup for a server

Btrfs is probably the most modern filesystem of all widely used filesystems on Linux. In this article we explain how to use Btrfs as the only filesystem on a server machine, and how that enables some sweet capabilities, like very resilient RAID-1, flexible adding or replacing of disk drives, using snapshots for quick backups and […]

World IPv6 Day and how to add IPv6 support to a web server

Today, 6th of June we celebrate World IPv6 day. Ipv6 is the new standard for IP protocols. IPv6 is important because, as everyone by now should know, the public IPv4 address space is running out. In fact all IPv4 address blocks have already been mostly consumed by registrars and the resource problem is being avoided […]

Linux and POWER8 microprocessors

Why POWER8? With the enormous amount of data being generated every day, POWER8 was designed specifically to keep up with today’s data processing requirements on high end servers. POWER8 is a symmetric multiprocessor based on the power architecture by IBM. It’s designed specifically for server environments to have faster execution times and to really concentrate performing well on […]

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The Best of 2015

  Another new year has started, and we think it is time to look a bit back and review what became the most popular content in Seravo Blog in 2015. Alltogether, in 2015, Seravo’s web page gained 233 681 visits and 196 401 users – these are pretty cool numbers for a modest sized company that we […]

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Using RAID with btrfs and recovering from broken disks

Btrfs (pronounced Better FS) is a relatively new filesystem that operates on the copy-on-write principle (abbreviated COW, which stems a more friendly pronunciation for btrfs: Butter FS). Btrfs includes a lot of interesting functionality and replaces traditional Linux disk and filesystem tools like LVM (volume manager, disk snapshots) and mdadm (software RAID). In RAID usage btrfs is much more flexible […]

Android Phone Review: The OnePlus X

OnePlus is a mobile phone manufacturer famous for selling the OnePlus One with pre-installed CyanogenMod, instead of a bloated custom Android as most manufacturers do. Their newest model OnePlus X was released on November 5th 2015 and after a few days of use, it seems to live up to its promises.

Fixing black screen after login in Ubuntu 14.04

How to fix black screen after login in Ubuntu 14.04? (Ohje suomeksi lopussa.) A lot of Linux-support customers have contacted us recently asking to fix their Ubuntu laptops and workstations that suddently stopped working. The symptom is that after entering the username and password in the login screen, they are unable to get in. Instead […]

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Cyberwar never ceases

A great deal of our work as Linux system administrators is related to security. Each server we maintain is bombarded on daily basis in a never ending cyberwar. Some of our customers (e.g. the website of the former Finnish Minister of Foreign Affairs, government websites, high profile political organisations and media sites) are obvious targets but […]

Ubuntu Phone and Unity vs Jolla and SailfishOS

With billions of devices produced, Android is by far the most common Linux-based mobile operating system to date. Of the less known competitors, Ubuntu phone and Jolla are the most interesting. Both are relatively new and neither one has quite yet all the features Android provides, but they do have some areas of innovation where […]

Continuous integration testing for WordPress plugins on Github using Travis CI

Intro We have open sourced and published some plugins on wordpress.org. We only publish them to wordpress.org and do the development in Github. Our goal is to keep them simple but effective. Quite a few people are using them actively and some of them have contributed back by creating additional features or fixing bugs/docs. It’s super nice to […]

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Ubuntu Phone review by a non-geek

  Few weeks ago I found a pretty black box waiting on my desk at the office. There it was, the BQ Aquaris E4.5, Ubuntu edition. Now available for sale all over Europe, the world’s first Ubuntu phone had arrived to the eager hands of Seravo. (Working in an open office with a bunch of […]

Why and how to publish a plugin at WordPress.org

The first ever WordCamp was held in Finland on May 8th and 9th in Tampere. Many from our staff participated in the event and Seravo was also one of the sponsors. On Friday Otto Kekäläinen had a talk with the title “Contributing to WordPress.org – Why you (and your company) should publish plugins at WordPress.org”. […]

WordCamp Finland 2015 brings WordPress enthusiasts together

WordCamps are casual, locally-organized conferences covering everything related to WordPress, the free and open source personal publishing software that powers over 75 million sites on the web. In May of 2015, WordCamp will finally have its debut in Finland. The event is set to take place at the home base of Seravo in Tampere. WordCamps come in all different flavours, based on the […]

OpenFOAM – Open Computational Fluid Dynamics

OpenFOAM (Open source Field Operation And Manipulation) is a numerical CFD (Computational Fluid Dynamics) solver and a pre/postprocessing software suite. Special care has been taken to enable automatic parallelization of applications written using OpenFOAM high-level syntax. Parallelization can be further extended by using a clustering software such as OpenMPI that distributes simulation workload to multiple […]

How to create good OpenPGP keys

The OpenPGP standard and the most popular open source program that implements it, GnuPG, have been well tested and widely deployed over the last decades. At least for the time being they are considered to be cryptographically unbroken tools for encrypting and verifying messages and other data. Due to the lack of easy-to-use tools and […]

10 reasons to migrate to MariaDB (if still using MySQL)

The original MySQL was created by a Finnish/Swedish company, MySQL AB, founded by David Axmark, Allan Larsson and Michael “Monty” Widenius. The first version of MySQL appeared in 1995. It was initially created for personal usage but in a few years evolved into a enterprise grade database and it became the worlds most popular open […]

Password hygiene – every man’s responsibility

Everybody knows what hand hygiene is: hands are disinfected every time we enter a hospital. In the same way as germ-free hands stops diseases from spreading, password hygiene helps to prevent the misuse of credentials. Password hygiene may feel useless when the effect is not immediately visible, but it is never the less very important […]

A guide to modern WordPress deployment (part 2)

Recently we published part one in this series on our brand new WordPress deployment platform in which we covered some of the server side technologies that constitute our next-gen WordPress platform. In part 2 we’ll be briefly covering the toolkit we put together to easily manage the Linux containers that hold individual installations of WordPress. […]