Archive for the ‘System Administrator Articles’ Category

Python for bash replacement

When I started learning Python, I was looking for a programming language that would replace BASH, AWK and SED. I am a C/C++ programmer and as such I better invest my time into studying C and C++. Instead, every time I needed some complex script I opened up a book on BASH and refreshed my […]

MSI-X – the right way to spread interrupt load

When considering ways to spread interrupts from one device among multiple cores, I can’t not to mention MSI-X. The thing is that MSI-X is actually the right way to do the job. Interrupt affinity, which I discussed here and here, has a fundamental problem. That is inevitable CPU cache misses. To emphasise this, think about […]

Why interrupt affinity with multiple cores is not such a good thing

One of the features of x86 architecture is ability to spread interrupts evenly among multiple cores. Benefits of such configuration seems to be obvious. Interrupts consume CPU time and by spreading them on all cores we avoid bottle-necks. I’ve written an article explaining this mechanism in greater detail. Yet let me remind you how it […]

Backup and restore your Linux installation

Table of contents Quick links Introduction Creating the backup What to backup Figuring out device file Preparations Actual backup Restoring from backup Preparations Restoring Restoring entire hard disk Restoring single partition Quick linksBACK TO TOC Backing up Restoring backup up disk Restore backed up partition IntroductionBACK TO TOC Backing up Linux installation and restoring it, […]

SSH crash course

About this article I would like to do two things in this article. First I would like to tell you about SSH. How to make it work. How to use public key cryptography to login to a remote computer. How to execute remote commands and copy files to/from a remote machine. On the other hand, […]

32bit vs 64bit computers, the QA

Table of contents Quick links Introduction Creating the backup What to backup Figuring out device file Preparations Actual backup Restoring from backup Preparations Restoring Restoring entire hard disk Restoring single partition Introduction Part 1. Basics Intro Connecting to remote host – simple case RSA/DSA host fingerprint What happens when host fingerprint changes How to handle […]

Swap vs. no swap

Table of contents Quick links Introduction Creating the backup What to backup Figuring out device file Preparations Actual backup Restoring from backup Preparations Restoring Restoring entire hard disk Restoring single partition Introduction Part 1. Basics Intro Connecting to remote host – simple case RSA/DSA host fingerprint What happens when host fingerprint changes How to handle […]

Few problems that you may encounter when booting Linux

Table of contents Quick links Introduction Creating the backup What to backup Figuring out device file Preparations Actual backup Restoring from backup Preparations Restoring Restoring entire hard disk Restoring single partition Introduction Part 1. Basics Intro Connecting to remote host – simple case RSA/DSA host fingerprint What happens when host fingerprint changes How to handle […]

sed – the missing manual

Table of contents Quick links Introduction Creating the backup What to backup Figuring out device file Preparations Actual backup Restoring from backup Preparations Restoring Restoring entire hard disk Restoring single partition Introduction Part 1. Basics Intro Connecting to remote host – simple case RSA/DSA host fingerprint What happens when host fingerprint changes How to handle […]

Opening and modifying the initrd

Table of contents Quick links Introduction Creating the backup What to backup Figuring out device file Preparations Actual backup Restoring from backup Preparations Restoring Restoring entire hard disk Restoring single partition Introduction Part 1. Basics Intro Connecting to remote host – simple case RSA/DSA host fingerprint What happens when host fingerprint changes How to handle […]