In this example, I will use the getent command to check if a Linux group exists. if getent group "$groupname" >/dev/null; then echo "Group $groupname exists" fi Replace $groupname with the name of the group you want to check. If you like to check if the group does not exist (e.g. because you like to ... Read more
Here I will show you how to check if a Linux user exists (or does not exist) in a POSIX-compatible shell like Bash or Dash. I will use the getent command along with the /etc/passwd file for this. Example Bash script: if getent passwd "$username" >/dev/null; then echo "User $username exists" else echo "User $username ... Read more
The bash history is a log file that contains all commands that a user executed on the Linux BASH shell. When you use the "arrow up" key on your keyboard, then Bash will look up the previous command from that file and display it on the screen. You just have to press "Enter" to execute ... Read more
Bash shell refers to Bourne Again Shell which can be found as the default shell in most of the Linux distributions. A Bash Script is a file where multiple shell commands are scripted to perform a particular task. If you are familiar with bash script then this article is for you, in this demonstration I ... Read more
In this guide, I will show you how to find your IP address (private IP address and public IP address) on Ubuntu Linux. I will also cover the steps for an IP location lookup to get IP location of my ipaddress, this will also show my isp. The same steps will work on other Linux ... Read more
Google Forms are very commonly used for surveys and questionnaires nowadays. Besides conducting such studies, they are also used in some educational institutions for quizzes and exams. This free web-based application offers us so much flexibility in designing and presenting questions that Google Form is the first name that comes to mind when we want ... Read more
Linux is a multi-user operating system. Whether it's using the superuser account to execute administrative tasks or modifying the current user's access to a certain directory, you'll have to move between users at some point. Linux has several options for dealing with such difficulties. The obvious solution is to log out and log in as ... Read more
Resetting your system's root password may be a necessary step if you have forgotten it or have bought a used computer that you don't want to set up a new one. Doing so without any installation medium saves you a blank CD and a bit of time. To start, restart your computer and get to ... Read more
Grub's default boot option is stored within a config file found on the partition where your Master Boot Record is located (if you had it installed previously, there may also be grub.cfg files on other partitions, but these won't affect boot sequence). Its direct path is /boot/grub/grub.cfg and it has to be opened as root, ... Read more
Linux user quotas can be edited with the commands edquota or setquota on the shell. While edquota opens the quota settings in an editor like vim, setquota allows you to specify the quota settings on the command line. Example for disabling the quota for the user "testuser": setquota -u testuser 0 0 0 0 -a ... Read more