How to check hard disk health on Linux using smartmontools

If there is something that you never want to happen on your Linux system, that is having hard drives die on you without any warning. Backups and storage technologies such as RAID can get you back on your feet in no time, but the cost associated with a sudden loss of a hardware device can […]
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How to create a software RAID-1 array with mdadm on Linux

Redundant Array of Independent Disks (RAID) is a storage technology that combines multiple hard disks into a single logical unit to provide fault-tolerance and/or improve disk I/O performance. Depending on how data is stored in an array of disks (e.g., with striping, mirroring, parity, or any combination thereof), different RAID levels are defined (e.g., RAID-0, […]
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How to diskless boot a Linux machine

Diskless booting implies that a client computer does not have any disk storage when booting an operating system. In that case, the computer can load the kernel as well as the root filesystem from a remote NFS server over network. It may use several different methods to load the kernel and the root filesystem from […]
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How to monitor system temperature on Linux

In most cases, you are not supposed to be worried about the temperature of your computer. Barring manufacturing defects, hardware is designed so that its temperature does not exceed maximum operating temperature. But even without any hardware fault, overheating can occur due to various software issues, e.g., buggy graphics card driver, misconfigured fan control program, […]
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What is a good HEX editor on Linux?

A hex editor is different from a regular text editor in that the former displays the raw binary content of a given file, without applying any text encoding or typesetting. A hex editor can be useful in various cases, e.g., repairing disk image and partition, reverse-engineering binary code, patching emulator ROM files, analyzing malware, etc. […]
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How to clean up disk space on Linux

If you have an aged Linux system, chances are that you have a lot of disk space wasted due to things like application-specific caches (e.g., browser caches), system caches (e.g., apt cache), unnecessary locale files or other temporary files. With so many different ways files are generated, it is hard to track down the wasted […]
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How to convert between VirtualBox VDI and VMware VMDK

There are several disk image formats used by virtualization software; VDI for Oracle VM VirtualBox, and VMDK for VMware vSphere, to name a few. If you want to convert VirtulBox VDI image to VMware VMDK image, or vice versa, there are two command-line utilities available to use. The first tool is VBoxManage, which is a […]
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How to monitor disk I/O in Linux from command line

If your Linux system gets slow down due to heavy disk I/O activities, you probably want to know which processes or users (in case of multi-user systems) are the culprit for such activities. You may also wish to monitor disk I/O trending over time as part of daily Linux system administration. Here I will introduce […]
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How to create an encrypted disk partition on Linux

Suppose you have a portable USB drive to use with your Linux system. If you are security conscious, you may want to encrypt your USB drive, so that no one else tamper with content in your USB drive. For that, you can use dm-crypt and LUKS, which together provide transparent encryption of block devices by […]
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