If you're a Linux newbie, you should know that there will be times - such as when installing packages - when you'll be looking for a way to see if your operating system is 32-bit or 64-bit. The information is not hard to find, but there is more than one way to access it. In ... Read more
The following command can be used to check and repair all MySQL databases on a Ubuntu or Debian Linux System. I've tested the commands on Ubuntu 20.04 and Debian 10. Repair MySQL databases on Ubuntu Linux sudo mysqlcheck --defaults-file=/etc/mysql/debian.cnf --auto-repair --optimize --all-databases MySQL database repair on Debian mysqlcheck --defaults-file=/etc/mysql/debian.cnf --auto-repair --optimize --all-databases The benefit of ... Read more
JPEG is a lossy compression file format for digital images. It can greatly reduce the amount of storage space used by a graphics file compared to the PNG format. This tutorial describes how to convert a PNG file to JPG on the shell. I use the GraphicsMagick command-line tool on my Ubuntu 20.04 system to ... Read more
I recently installed Ubuntu on my desktop computer. Everything was working fine, except that I was not able to capture screenshots using the 'Insert/Print Screen' key on my Dell keyboard. While googling the issue, I stumbled upon a workaround that solved my problem. The workaround was to create a custom keyboard shortcut. If you are ... Read more
The ps command in Linux, as you might already know, is one of the most frequently used command-line tools. For the uninitiated, the utility basically reports a snapshot of the current processes on the system. The ps command provides a plethora of options, and as you might agree, it's not possible to know about or ... Read more
Mostly, we have only a single display connected to computer systems. However, you can have multiple displays connected to a system. While working with more than one display, sometimes you might find yourself in a situation where-in you need to perform a display-specific task. For example, taking a screenshot. In these scenarios, you need to ... Read more
Some internet access providers have port 25 disabled in their routers to prevent spam. If you run your own email server in a data center, you might have to enable the submission port (587) in postfix to be able to send emails from your local email client to your own mail server. Enable Submission Port ... Read more
When you get the error message "system-config-firewall: command not found" on your CentOS Server while trying to configure the firewall on the shell, then the text interface version of the firewall configuration utility is missing. Install CentOS Firewall configuration tool Install it with this command: yum install system-config-firewall-tui
The current status of a Linux software raid is written to the virtual file /proc/mdstat. You can view the status on the shell easily with the cat command: cat /proc/mdstat The output will look similar to this: Personalities : [raid0] [raid1] [raid6] [raid5] [raid4] md2 : active raid1 sda3[0] sdb3[1] 726266432 blocks [2/2] [UU] md1 ... Read more
If a process is shown with process state "D" in tools like ps or top, then it's an uninterruptable process. Example: ps axl | grep D F UID PID PPID PRI NI VSZ RSS WCHAN STAT TTY TIME COMMAND 4 104 2579 9109 20 0 5024 2116 refrig D ? 0:00 cleanup -z -t unix ... Read more