Linux

Screen command offers the ability to detach a long running process (or program, or shell-script) from a session and then attach it back at a later time. When the session is detached, the process that was originally started from the screen is still running and managed by the screen. You can then re-attach the session [...]

Fail2ban scans log files for various services ( SSH, FTP, SMTP, Apache, etc., ) and bans the IP that makes too many password failures. It also updates the firewall rules to reject these ip addresses. Fail2ban is an intrusion prevention framework written in the Python programming language. Main purpose of Fail2ban is to prevent brute [...]

We are Vim editor fans. Vim editor is the most popular editor for UNIX / Linux platform, followed by emacs editor. If you talk to emacs editor fans, they might think otherwise. In the spirit of learning, we’ve decided to explore emacs editor in detail and we’ll be posting several emacs articles in the upcoming [...]

For finding difference between two versions of a file on Linux, you can use any one of the 4 tools explained in this article — diff, colordiff, wdiff, and vimdiff. The screenshots provided for these tools shows the difference between the following two empfile1.txt and empfile2.txt. $ cat empfile1.txt John Smith 1001 Sr. Engineer Peter [...]

Looping statements are used to force a program to repeatedly execute a statement. The executed statement is called the loop body. Loops execute until the value of a controlling expression is 0. The controlling expression may be any scalar data type. The shell language also provide several iteration or looping statements. In this article let [...]

Question: When I try to launch any GUI application on a remote server, I’m getting the “cannot open display:” error, as shown below. How do I fix this? For example, while launching the gedit on remote server, I got the following message. (gedit:3658): Gtk-WARNING **: cannot open display: I get similar message when I try [...]

As part of the on-going VMware article series, earlier we discussed about VMware virtualization fundamentals, and how to install VMware Server 2. In this article, let us discuss about how to install VMware ESXi. VMware ESXi is free. However, the software comes with a 60 days evaluation mode. You should register on VMware website to [...]