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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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Article Archive for April 2011

Load-Testing HPC Linux Clusters with “stress”

April 28, 2011 – 8:43 pm

The “stress” is a simple-to-use load generator for POSIX systems that I found very useful for stress-testing HPC clusters. The current version of the application is 1.0.4 and it was easy to compile and install. Stress can create configurable system load for CPU, memory, I/O, and disks. In the example below we ran “stress” on a SLES 11 HPC cluster with HP CMU 4.2 installed.

Facebook Security for the Lazy

April 28, 2011 – 2:36 am
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Every time you use Facebook, you probably have a nagging feeling in the back of your head that someone other than your friends is reading your posts. You should trust that feeling. At the same time, keep in mind that Facebook is a tool designed primarily for sharing personal information with large groups of people you barely know. Facebook is not your personal diary or a substitute for SMS. You just need to assume that everything you post on Facebook inevitably will end up in the hands of someone you don’t like very much. And then you proceed based on that assumption.