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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.

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Articles in SysAdmin

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 …

iPhone: No Clicking Sound

July 16, 2009 – 4:58 am
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Many long-time iPhone users are familiar with the mystery of disappearing keyboard clicking sounds (among other sound effects). Here are a few things you can try before you take your fruity phone back to the …

The Follies of Traffic Driving

July 11, 2009 – 4:31 pm
Traffic light for bikes.

Imagine a busy street in the city with sidewalks packed with pedestrians. Hundreds of people are pushing and shoving, eating, arguing, talking on their cell phones and not paying any attention to each other. Suddenly, …

Testing Filesystem Performance with Bonnie++

July 10, 2009 – 4:33 pm
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Bonnie++ is a benchmark utility designed to test performance of hard drives and filesystems by simulating various types of disk I/O. Bonnie++ may be used to test local disks as well as network-mounted filesystems. It …

Tracking Prices of Hard Drives

July 5, 2009 – 5:40 pm

It seems that only a year ago terabyte hard drives were a novelty item. Today they are on clearance at computer stores trying to free up the shelves for 1.5Tb drives and the 2Tb hard …

Wget and User-Agent Header

June 29, 2009 – 12:41 pm
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As you may already know, Wget is a popular (particularly in the Unix world) command-line downloader and Web crawler application. You can read more about Wget in one of my earlier posts on the subject. …

Numeric File Permissions in Unix

June 27, 2009 – 7:50 pm
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Suppose you are working with a Web server and your task is to make sure that no files or directories have permissions “777”. It would be easy to just recursively change permissions for all files …

Duplicating WordPress Installation

June 25, 2009 – 2:51 pm
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Whenever you upgrade your WordPress installation or do development work, it is always a good idea to be working on a copy of your main site and not on the real thing. Copying WordPress installation …

Restart Apache, MySQL When Low on Memory

June 25, 2009 – 4:27 am
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Heavy traffic, hungry SQL queries, leaky applications will eventually leave your server low on memory. Apache will go on a hunt for swap space and MySQL will start freezing in thoughtful contemplation. Your hard drives …

MySQL Global Search and Replace Script

June 25, 2009 – 3:53 am
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A day will eventually come when your need to find and replace a string of text in your database. You don’t know which row, or which column, or which table. Heck, you may not even …

Passing MySQL Commands from Shell Script

June 25, 2009 – 3:30 am
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Running MySQL commands from a shell script is a relatively simple task that has a lot of people baffled. Some say its too complicated and suggest using PHP or Perl, others claim doing so is …

WordPress Directory Listing Risk

June 11, 2009 – 11:36 pm
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A large number of WordPress directories do not have an index file. This is particularly dangerous in case of the plugins directory. If your server allows directory listings, a potential attacker may see which plugins …

DownThemAll! “No free space” error

May 18, 2009 – 6:12 pm
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DownThemAll! is a popular download manager for Firefox Web browser supporting multi-part downloading with ability to pause and restart downloads without losing data. A common problem encountered while using DownThemAll! is the dreaded “no free …

Controlling Process CPU Utilization

March 9, 2009 – 12:36 pm
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Let’s say there is a process on your Unix/Linux system that sometimes tends to consume all CPU resources and become unresponsive. At the same time, you do not want to terminate the process at the …

Encoding Videos for XBox 360 and PS3

January 1, 2009 – 4:47 pm

Both Xbox 360 and PS3 support a variety of video codecs and are capable of playing high-definition video files. One of the most popular formats for HD video files is Matroska (MKV), which provides excellent …

Linux and High I/O Wait

December 21, 2008 – 12:07 am
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When you look at the CPU activity of your computer, one of the parameters is the iowait. This value shows how much time your CPU wastes while it is waiting for I/O operations for complete. …

Sharing Videos from Linux to Xbox 360

December 19, 2008 – 8:49 pm
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Xbox 360 uses UPnP protocol to stream multimedia files from computers on your home network. Normally, you would have a Windows PC running WMP and sharing files. But what if you have a Linux box …

What’s the Best CMS

July 29, 2008 – 2:57 pm

Content management systems are sprouting up like mushrooms after a warm April rain. If your job is to find the perfect CMS for your needs, you can spend weeks analyzing and comparing features of various …

Partitioning System Disk

July 24, 2008 – 8:25 pm
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When performing a new Unix OS installation you are usually presented with a choice of accepting the default partitioning layout or going into advanced settings and defining your own partitions. The default layout will normally …

Google Tips and Tricks

July 22, 2008 – 11:15 am
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Google offers a remarkable set of powerful features. Unfortunately, most people are not aware of these possibilities. They use only the most basic functionality offered by Google and then waste their time on weeding out …

Convert Images to PDF

July 18, 2008 – 12:26 am
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Converting sets of images into multi-page PDF files makes it easier to organize and share them. All you need for the conversion is the free that will run on your Windows, Linux, MacOS and many other operating systems. If you are running a recent version of Linux, chances are that ImageMagick is already installed on your computer (just type “which convert” to check).

Best of Web Design

June 24, 2008 – 2:41 pm

As more Web surfers get high-speed access, Web designers are tempted to go overboard with multimedia sites that waste your time and distract you from the content. This little collection of Web designs is proof …