CentOS and RHEL 7 Restart, Stop, Start Networking Commands

I recently installed CentOS Linux version 7 or Red Hat Enterprise Linux version 7. How can I restart networking service using command line options? How can I start / stop and restart networking service on a CentOS/RHEL 7 based system?CentOS 7 / RHEL 7 / Fedora Linux (many other modern distor) uses Systemd. It is a system and service manager …

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UNIX Date Command Examples

How do I view and set date under UNIX operating systems? The date command under UNIX display date. It is also used to set date and time. You must be the super-user (root) to change the date and time. UNIX Date Command Syntax date date "+format" Task: Display Current Date and Time Type the following command: date Sample outputs: Tue …

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Display Hard Disk Specs and Details on Linux

Linux comes with various commands to find out information about your hard drive. I recommend hdparm command which provides a command line interface to various hard disk ioctls supported by the stock Linux ATA/IDE device driver subsystem. This command read / request identification information such as disk size, description and much more directly from the drive, which is displayed in …

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HowTo Run a Script In Linux

How do I run a Linux shell script? How can I run a script in Linux? By default script will not run. You need to set execute permission for your script. To execute or run script type the following command: chmod +x script-name-here OR chmod 0755 script.sh Use the ls command to view permission on the script: $ ls -l …

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11 useful commands for Linux/Unix administrators

Command line is more powerful because you can do  lot with them,  you can tell your computer exactly what you want and get the appropriate answer, while GUI application can only tell your computer what the GUI programmer has defined.  Recently, CLI is mostly used by Linux/Unix administrators since most popular linux distros come with a complete set of GUI applications that …

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Avoiding CPU Speed Scaling – Running CPU At Full Speed

If you have a server on collocation with the super-fast CPU, that doesn’t mean that you get it running at full power. Here is a preamble. When doing inventory of Linux servers, that I’m administering, I’ve found that some of them are running on lower CPU speed, then they could. This can be easily checked with this command: #grep -E …

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How to install cron (crond, crontab) in CentOS

Cron is a daemon that can be used to schedule the execution of recurring tasks according to a combination of the time, day of the month, month, day of the week, and week. This is how I install crond onto my CentOS server edition as it doesn’t seem to come preinstalled, this might not be true for other distributions and …

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