How to diagnose OOM errors on Linux systems

Out-of-memory (OOM) errors take place when the Linux kernel can’t provide enough memory to run all of its user-space processes, causing at least one process to exit without warning. Without a comprehensive monitoring solution, OOM errors can be tricky to diagnose. In this post, you will learn how to diagnose OOM errors in Linux kernels […]

Linux benchmark scripts and tools

This list of Linux benchmark scripts and tools should prove helpful for quick performance checks of CPU, storage, memory, and network on Linux servers and VPS. Check each script before running from the command line. Most of these scripts will benchmark the CPU, memory, storage, and network. In most cases, the CPU Model, frequency, number […]

Your Web Host Doesn’t Want You To Read This: Benchmark Your VPS

Sept 27th, 2021: Added link to a great list of command-line benckmark scripts. June 17th, 2019: Added instructions for network speed test using speedtest-cli script. Nov 2nd, 2016: Included quick dd commands to check cached vs. uncached read performance. This article will highlight using the ‘dd’ Unix command for a quick benchmark of your Linux […]

atop – For Linux server performance analysis

We’re all familiar with top, a real-time system monitor. Some prefer htop and previously, I mentioned iotop for use with storage read/write monitoring. Let’s looks at another popular tool for Linux server performance analysis: atop.   Advantages of atop Atop is an ASCII full-screen performance monitor which can log and report the activity of all server processes. […]

htop: Quick Guide & Customization

htop is an interactive system monitor, but also a process-viewer, process-manager, strace tool and more. Sysadmins may opt to use htop when Unix top does not provide enough information about system processes. htop uses a cursor-controlled interface for sending signals to processes. One example where this comes in handy is: you don’t have to type […]

Free vs. Available Memory in Linux

At times we will need to know precisely how our Linux systems use memory. This article will examine how to use the free command-line utility to view memory usage on a Linux system. In doing so, we will clearly define the difference between free vs. available memory on Linux systems.   Free vs. Available memory […]

90 Linux Commands frequently used by Linux Sysadmins

There are well over 100 Unix commands shared by the Linux kernel and other Unix-like operating systems. If you are interested in the commands frequently used by Linux sysadmins and power users, you’ve come to the place. Recently, I published a five-part series covering commands often used by Linux sysadmins. Below I’ve listed the 90 […]

Linux Commands frequently used by Linux Sysadmins – Part 2

Last week, I published part 1 of this five-part series entitled: Linux Commands frequently used by Linux Sysadmins. That first article scratched the surface of what I believe are 50 to 100 commands used often by Linux Sysadmins and power users. Also, see Part 3, Part 4, and Part 5. Let’s jump into another set of commands and command-line […]

SCP Linux – Securely Copy Files Using SCP examples

This post includes SCP examples. SCP or secure copy allows secure transferring of files between a local host and a remote host or between two remote hosts. It uses the same authentication and security as the Secure Shell (SSH) protocol from which it is based. SCP is loved for it’s simplicity, security and pre-installed availability. […]

Linux Commands frequently used by Linux Sysadmins – Part 1

What are some of the Linux commands used by Sysadmins and power users daily? In this article, I’ve listed 10 such commands frequently used. Suggestions, and feedback welcome. Also, see Part 2, Part 3, Part 4, and Part 5. Some people consider Linux to be a complicated operating system, geared toward expert users only. However, as […]