Keyboard cleaning 101
Step-by-step instructions on how to clean your keyboard.
Linux-natives blog: Linux and open source – technology and strategy
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 […]
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 […]
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 […]
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 […]
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”. […]
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 […]
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. […]
A guide to modern WordPress deployment (part 1)
As a Linux and open source specialist company, Seravo provides services to many companies that run Linux in a web server. Not surprisingly, in many of these cases, the top-level software running on the server is of course, the world’s most popular CMS, WordPress. We love it!
Turn any computer into a wireless access point with Hostapd
Do you want to make a computer function as a WLAN base station, so that other computers can use as it as their wifi access point? This can easily be done using the open source software Hostapd and compatible wifi hardware. This is a useful thing to do if computer acting as a firewall or […]
Optimal Sailfish SDK workflow with QML auto-reloading
Sailfish is the Linux based operating system used in Jolla phones. Those who develop apps for Jolla use the Sailfish SDK (software development kit), which is basically a customized version of Qt Creator. Sailfish OS apps are written using the Qt libraries and typically in the C++ programming language. The user interfaces of Sailfish apps […]
Open source for office workers
Open source software is great and it’s not only great for developers who can code and use the source directly. Open source is a philosophy. Open source is for technology like what democracy is for society: it isn’t magically superior right away, but it enables a process which over time leads to best results – […]
How’s (battery) life with Jolla?
Some years ago Nokia conducted a large survey among its customers on what people most liked about Nokia phones. One of the top features turned out to be their unrivaled battery life. Despite the hype around screen resolutions, processor performance and software versions, one of the most important features for a mobile device is simply […]
Installing Node.js on SUSE Linux Enterprise
The officially supported collection of software in SUSE Linux Enterprise Linux 11 Service Pack 3 does not contain all conceivable Linux software, but in the Open Build System there are tons of software that is build for SLES 11SP3. Installing these software packages and repositories is of course on your own risk, as they are […]
The Jolla phone – first impressions
The first device running SailfishOS, the successor of Meego, has finally been released. It’s elegant and beautiful both on the outside and inside. It has multiple unique features that makes it unlike any mobile device we’ve seen so far. We have been waiting for Jolla to release their phone for more than a year and […]
Dual-booting Ubuntu 12.04 and Windows 8 with Restricted Boot
In parallel with the introduction of Windows 8, Microsoft also introduced new hardware requirements to all manufacturers who sell pre-installed Windows 8 computers. As Microsoft Windows still has a monopoly in the desktop and laptop computer market, lots of people who buy computers suffer from a new anti-feature Microsoft introduced: Secure Boot. All Windows 8 […]