What is a good command-line calculator on Linux

Every modern Linux desktop distribution comes with a default GUI-based calculator app. On the other hand, if your workspace is full of terminal windows, and you would rather crunch some numbers within one of those terminals quickly, you are probably looking for a command-line calculator. In this category, GNU bc (short for “basic calculator”) is […]
Continue reading…

 

How to verify the authenticity and integrity of a downloaded file on Linux

When you download a file (e.g., an installer, an ISO image, or a compressed archive) from the web, the file can be corrupted under a variety of error conditions, e.g., due to transmission errors on the wire, interrupted download, faulty storage hardware, file system errors, etc. Such failure cases aside, a file can also be […]
Continue reading…

 

How to speed up slow apt-get install on Debian or Ubuntu

If you feel that package installation by apt-get or aptitude is often too slow on your Debian or Ubuntu system, there are several ways to improve the situation. Have you considered switching default mirror sites being used? Have you checked the upstream bandwidth of your Internet connection to see if that is the bottleneck? Nothing […]
Continue reading…

 

How to convert image, audio and video formats on Ubuntu

If you need to work with a variety of image, audio and video files encoded in all sorts of different formats, you are probably using more than one tools to convert among all those heterogeneous media formats. If there is a versatile all-in-one media conversion tool that is capable of dealing with all different image/audio/video […]
Continue reading…

 

How to set up EPEL repository on CentOS

If you are using CentOS or RHEL, it is strongly recommended that you configure EPEL (Extra Packages for Enterprise Linux) repository on your system. EPEL is a community effort to create a repository of high-quality add-on free software packages for RHEL-based distributions. Once you set up EPEL repository, you can use yum command to install […]
Continue reading…

 

How to create a cloud-based encrypted file system on Linux

Commercial cloud storage services such as Amazon S3 and Google Cloud Storage offer highly available, scalable, infinite-capacity object store at affordable costs. To accelerate wide adoption of their cloud offerings, these providers are fostering rich developer ecosystems around their products based on well-defined APIs and SDKs. Cloud-backed file systems are one popular by-product of such […]
Continue reading…

 

Linux TCP/IP networking: net-tools vs. iproute2

Many sysadmins still manage and troubleshoot various network configurations by using a combination of ifconfig, route, arp and netstat command-line tools, collectively known as net-tools. Originally rooted in the BSD TCP/IP toolkit, the net-tools was developed to configure network functionality of older Linux kernels. Its development in the Linux community so far has ceased since […]
Continue reading…

 

How to manage LVM volumes on CentOS / RHEL 7 with System Storage Manager

Logical Volume Manager (LVM) is an extremely flexible disk management scheme, allowing you to create and resize logical disk volumes off of multiple physical hard drives with no downtime. However, its powerful features come with the price of a somewhat steep learning curves, with more involved steps to set up LVM using multiple command line […]
Continue reading…

 

How to use on-screen virtual keyboard on Linux

On-screen virtual keyboard is an alternative input method that can replace a real hardware keyboard. Virtual keyboard may be a necessity in various cases. For example, your hardware keyboard is just broken; you do not have enough keyboards for extra machines; your hardware does not have an available port left to connect a keyboard; you […]
Continue reading…