what are linux commands and the 4 types of them

shell commands that are builtin to the shell

In Linux or any unix based system, a command refers to a directive that can used to invoke computer program. This program then acts as an interpreter to the command and its options and arguments, and performs a specific task. In most scenarios, a command refers to a directive in the command line which is usually a shell such as…

how to access ftp servers and transfer files in linux without an ftp client

accessing ftp server using dolphin in kde

Many times softwares are hosted on ftp servers, especially open source and not so popular ones. FTP servers are also good method to transfer files and folder between machines. This means that you will need to occasionally connect to FTP file servers either to download or upload files. If you happen to work with FTP servers a lot, then it…

how to configure proxy server in kde

kde network and proxy server settings in system settings dialog

Depending on the network you are connected to, you may need to configure a proxy server in order for you to connect to the internet. A proxy server is not a part of every network and is not a required component of a network. Large networks, such as corporate networks usually have a proxy server that allows the network traffic…

how to enable and disable web directory listing on your web server

directory listing configuration in web.xml

The web server that you use to host your website has not only the ability to render and display web pages but also the ability to display directories and it content. This feature is also referred to as the directory listing of the server. To be honest, there is usually never a reason to enable the directory listing for a…

how to change port number of ftp (vsftpd, ProFTPd) in linux

linux ftp server port configuration

One of the most popular methods of transferring files between machines is using a FTP server and client. There are quite a few FTP servers out there, and almost all of the Linux distros comes with one by default. If you are not happy with the one that is installed by default, you can always install another one. By default,…

url canonicalization: how it affects seo and how to fix it

Inlining css in html helps with SEO

URL Canonicalization is the process where by a resource that has multiple URL or URIs pointing to it is standardized to a single URL. The process does not involve removing or changing the other URLs, but just designating one of the URLs as the “normal” or “standard” URL. The process is also known as normalization or standardization. For example, your home…

what is a robots.txt file and how it affects search engine indexing

webmaster tools robots.txt console

The robots.txt is a text file that resides in the top level folder on your webserver. The purpose of the robots.txt file (or just robots file) is to provide some guidance to search engine crawlers as to what should be crawled and indexed, and what content should not be crawled. The robots.txt file uses an exclusion standard, which means that you…

4 advanced calculators that you can use from linux command line

qalc or qalculate calculator in linux command line

Almost all modern day Linux distros come with a calculator application by default, unless you use Gentoo, Arch or a similar distro. Most times such GUI based calculator are sufficient to do some quick calculations. However you may not have access to a GUI based system all the time, and you would want to use a command line based calculator…

how to change the default ssh port in linux

linux change default port

One of the best ways to connect to a remote machine is by using the ssh protocol. Secure Socket Shell (or ssh) is a cryptographic network protocol that allows you to securely connect to a remote machine. It also refers to a suite of utilities that implement the protocol, such as the ssh server and an ssh client. In order for…

how to delete private data from mozilla firefox when you close the browser

firefox custom privacy

Mozilla Firefox is one of the most popular web browsers in the world. As with any web browser there is a lot of data collected as you browse the web. These set of data contains many different types of information: the browsing history, the site cookies, the cache, and personal data among others. Many times you might want to delete…

how to find all files containing specific text in a linux filesystem?

search text in file content with grep

Most search utilities work by crawling, parsing and generating an index of the file content so that they can be searched later. Many operating systems and desktop environment follow this approach to make searching faster. We will see how to search through file content from the command line, without the use of such indexes or engines. Needless to say, these…

how to forward ports on a network router

port forwarding for age of empiers

Network Routers are an integral part of your home network. Most applications and services works without having to open up ports on your router. But sometimes there are some applications, such as multiplayer games, p2p networks and web servers that necessitates the need for certain ports to be open or forwarded so that they can function correctly. The network router…