Check your disk usage with df and du

As system administrator , but also as common user on my PC, one of the more common problem is when a file system got filled up at up at 100% of its size.
So, in this article we’ll see 2 commands that can help us in keeping under control or check the space used in every filesystem and in his directory.

df : report file system disk space usage

du: estimate file space usage

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How to add swap to a KVM VPS or Dedicated Server CentOS 6

Swap is beneficial, because it allows inactive memory blocks to be written to disk, freeing up real memory for stuff like file system caching. Swap also (to some extent) protects you against short bursts of memory demand. Linux (by default) over commits real memory, relying on the fact that most applications ask for more than they need, but if they suddenly all need that memory swap can buffer you against applications crashing.

The first thing we need to do is check to see if any swap files have already ben enabled. So login to shell as the root user and run:

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GNU ddrescue – The Best Damaged Drive Rescue

When you rescue your data from a dying hard drive, time is of the essence. The longer it takes to copy your data, the more you risk losing. GNU ddrescue is the premium tool for copying dying hard drives, and any block device such as CDs, DVDs, USB sticks, Compact Flash, SD cards — anything that is recognized by your Linux system as /dev/foo. You can even copy Windows and Mac OS X storage devices because GNU ddrescue operates at the block level, rather than the filesystem level, so it doesn’t matter what filesystem is on the device.

 

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How to Install a CentOS 7.3 Minimal Server

This document describes the installation of a CentOS 7.3 server. The purpose of this guide is to provide a minimal setup that can be used as basis for our other tutorials here at howtoforge like the perfect server guides or the SAMBA, LAMP and LEMP server tutorials.

 

Requirements

To get started with the CentOS 7.3 installation, we will need the installer ISO file. This can either be the CentOS minimal ISO or the DVD ISO file. If you plan to install just this one server then choose the minimal ISO as it is a smaller, the installer will download the required packages during installation later. I will install several servers with CentOS 7.3, therefore I choose the DVD installer ISO so I dont have to download the same packages again for each server. Continue reading “How to Install a CentOS 7.3 Minimal Server”