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April 16, 2013 – 12:39 pm |

Imagine you have an HPC cluster with a hundred compute nodes named node001-node100. The two commands below will help you generate a list of node names – either all name on one line or one name per …

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Articles tagged with: awk

Duplicating WordPress Installation

June 25, 2009 – 2:51 pm | 5 Comments
Duplicating WordPress Installation

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 | 17 Comments
Restart Apache, MySQL When Low on Memory

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 | 15 Comments
MySQL Global Search and Replace Script

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 …

Controlling Process CPU Utilization

March 9, 2009 – 12:36 pm | 5 Comments
Controlling Process CPU Utilization

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 …

Sharing Videos from Linux to Xbox 360

December 19, 2008 – 8:49 pm | 3 Comments
Sharing Videos from Linux to Xbox 360

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 …

Useful SysAdmin Scripts: Search-and-Replace

June 1, 2008 – 3:03 pm | 2 Comments
Useful SysAdmin Scripts: Search-and-Replace

Let’s say you moved your server to a new network and now it has a different IP address. You know your users have a habit of hard-coding the server’s IP into their scripts. So you …

Creating print.css for WordPress

May 24, 2008 – 6:35 pm | 5 Comments
Creating print.css for WordPress

Many WordPress theme designers choose to cut some corners with their creations. One of the more important things they skip over is print.css – the stylesheet that controls your blog’s appearance when you print it. …

Passing shell variables to awk and sed

December 2, 2005 – 10:23 am | One Comment
Passing shell variables to awk and sed

By default awk and sed do not expand shell or system variables and do not pass their own variables back to the shell. To use shell variables awk and sed statements must be included in …

Wget examples and scripts

November 27, 2005 – 3:19 pm | 27 Comments
Wget examples and scripts

Wget is a command-line Web browser for Unix and Windows. Wget can download Web pages and files; it can submit form data and follow links; it can mirror entire Web sites and make local copies. …

Find largest files

November 19, 2005 – 11:17 pm | 3 Comments
Find largest files

How to find the largest files in the directory tree on Solaris.

Count users with “last”

November 19, 2005 – 11:15 pm | 5 Comments
Count users with “last”

Here is a quick example showing how to count users logged in on a particular date using the “last” command on Linux.