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March 2, 2022 – 2:00 pm

Books have been written on the subject of awk and sed. Here’s a small sample of commands I put together over the years that are useful for everyday system administration tasks. Most of these tasks …

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Networking

Unix and Linux network configuration. Multiple network interfaces. Bridged NICs. High-availability network configurations.

Applications

Reviews of latest Unix and Linux software. Helpful tips for application support admins. Automating application support.

Data

Disk partitioning, filesystems, directories, and files. Volume management, logical volumes, HA filesystems. Backups and disaster recovery.

Monitoring

Distributed server monitoring. Server performance and capacity planning. Monitoring applications, network status and user activity.

Commands & Shells

Cool Unix shell commands and options. Command-line tools and application. Things every Unix sysadmin needs to know.

Upgrading from Vista to Windows 7

January 27, 2010 – 10:45 pm

Recently I upgraded a client’s Vista computer (Toshiba Qosmio, 4Gb, Intel Core Duo P7350, 7200-RPM 200-Gb disk) from Vista Ultimate 64-bit to Windows 7 Ultimate 64-bit. Being a Unix sysadmin this is not something I usually do. How did the experience compare to upgrading HP-UX, Solaris or SLES? In a nutshell: I’d rather walk around all day in wet underwear than attempt to upgrade Vista ever again.

Windows Network Troubleshooting Script

January 20, 2010 – 10:15 pm
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I try my best to stay away from Windows. I wish my clients did the same. The usual difficulty of troubleshooting elusive network performance problems is amplified many-fold when there is a Windows computer at the end of the line. With Unix it’s relatively simple: run tests “a”, “b”, “c”, etc and follow the familiar process of elimination. With Windows in the picture the number of steps uses up all of the English alphabet and spills over well into the Russian one. And when you finally reach step “я”, you have to pull out your Chinese dictionary.

NetBackup Command Guide

December 27, 2009 – 7:17 pm
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NetBackup is an enterprise-level distributed backup and recovery application. The environment consists of the master server, media server, storage library, networking hardware, and client agents. NetBackup supports a wide variety of Unix, Linux, VMS, and Windows systems. The original backup solution was developed by Control Data Corp., later acquired by Openvision, which gave the product its “NetBackup” name. NetBackup was then bought by Veritas and is currently owned and supported (poorly) by Symantec.

Copying Data: Are We There Yet?

December 27, 2009 – 7:12 pm

I am sure this will sound familiar: you are copying a large amount of data – either locally or over the network – and you are wondering how long it will take and if there is a way to make things go faster.You may be surprised, but it does matter what type of files you are copying: 1Gb-worth of many small files will take considerably longer to copy than two 500Mb files. The hardware you are using is an important consideration, but it’s not the only factor limiting data transfer speed.

WordPress File Upload Size Limit

December 25, 2009 – 9:24 pm
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By default, WordPress will not allow you to upload a file larger than 2Mb. This limit is not set by WordPress itself, but by detaul PHP configuration. This configuration file is usually /etc/php.ini, but normally …

Building a Home Theater Computer

December 24, 2009 – 7:23 am

Ever wanted to build a kick-ass home theater computer? Here we have some highly detailed instructions for putting together just such a device. It is not a DVR like TiVo or your Verizon HDTV box. …

Working with Linux Driver Modules

December 22, 2009 – 6:57 pm
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You just replaced a failed network card, rebooted your server and now network wouldn’t start and your screen is filled with cryptic error messages about some kernel module doing something it’s not supposed to do. …

XBMC Home Theater Software

December 17, 2009 – 12:51 am

Printing from SuSE/SLES to a Windows Printer

December 10, 2009 – 5:05 pm

The following document explains how to configure your SuSE or SLES system to be able to print to a remote printer shared from a Windows server. The first step is to install Unix print support …

Reboot Remote Windows Workstation

December 10, 2009 – 9:53 am
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When using RDP, sometimes the session may lock up and you may need to reboot your workstation remotely. This can be done using the “shutdown.exe” command from your local PC. First, make sure you can …

Remove Duplicate Posts in WordPress

December 5, 2009 – 10:28 pm
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Below is the SQL script that will attempt to identify and remove duplicate posts in your WordPress database. This script can be useful for autoblogging. If you use plugins like WP-o-Matic to pull full-text RSS …

Slow SSH login in SuSE Linux

November 3, 2009 – 6:17 pm
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Starting with SuSE 10 and including both openSuSE and SLES an annoying SSH problem appeared. When you SSH to the server (via PuTTY and such) you get the “login” prompts right away, but the “password” …

How to Interview a Unix SysAdmin

October 31, 2009 – 2:16 am
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“You see,” he explained, “I consider that a man’s brain originally is like a little empty attic, and you have to stock it with such furniture as you choose. A fool takes in all the …

WordPress Backup Script

October 23, 2009 – 1:04 pm
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Whenever a new WordPress version comes out, I get an itch to upgrade as quickly as possible. Generally, this is not a good idea, unless you enjoy working out new software bugs and dealing with …

Shell Scripting for HPC Clusters, Part 2

October 23, 2009 – 12:30 pm
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This is the second installment of a multipart guide for beginner Unix sysadmins supporting HPC clusters. You can view the first part of the guide here.
Searching, Replacing, Comparing
Try to work with a large cluster and …

Shell Scripting for HPC Clusters, Part 1

October 10, 2009 – 12:59 am
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This is the first installment of a multipart guide for beginner Unix sysadmins supporting HPC clusters.
“For” and “While” Loop Constructs
The main challenge of supporting a Linux cluster is ensuring a homogeneous environment. Aside from small …

Web Hosting Providers and php.ini

October 9, 2009 – 4:07 pm
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The php.ini is the primary configuration file for the PHP – a popular scripting language used for Web development. Most Web hosting providers offer preinstalled PHP on their servers. If your search on PHP has …

iPhone Photography: Making Photos Better

September 17, 2009 – 9:05 pm
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The is the first installment of the three-part review of the better photo apps for iPhone. In the follow-up reviews we will look at artistic photo filters and panorama applications. If you don’t want to …

More Bad iPhone Apps

August 13, 2009 – 1:19 am
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This is the second part of my review of iPhone apps unworthy of your ninety nine cents. You can read the first part here.
Certain applications are well-written and might have been quite useful, if …

Automatically Validate HTTP Proxies

August 5, 2009 – 4:14 pm
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Let’s say you downloaded a long list of Web proxy servers. Now you are stuck with the task of weeding out the proxies that are dead, slow, fake, or otherwise unusable. There are some applications …

Shell Random Number Generator

August 4, 2009 – 2:58 pm
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Sometimes, in the course of writing shell script, a need arises for some random input. Using the built-in $RANDOM shell variable will give you a random number from 0 to 32767 . Let’s take a …

Bad iPhone Apps

July 29, 2009 – 4:37 pm
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Oh quit your whining, you will say, they are just a couple bucks each, so no big loss if some iPhone apps turn out to be trash. True, but they are so addictive. My first …