by Ramesh Natarajan
on August 8, 2011
Bash history is very powerful. Understanding how to effectively use the bash history expansions will make you extremely productive on the Linux command line.
This article explains 15 examples that uses the following bash history expansion features:
- Event designators – Refers to a particular command in the history. It starts with a !
- Word designators – Refers to a particular word of a history entry. Typically this gets combined with an even designator. Even designators and word designators are separated by a colon
- Modifiers – Modifies the result of the substitution done by the event or word designators
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by Ramesh Natarajan
on August 1, 2011
If you spend lot of time in Linux environment, it is essential that you know where the log files are located, and what is contained in each and every log file.
When your systems are running smoothly, take some time to learn and understand the content of various log files, which will help you when there is a crisis and you have to look though the log files to identify the issue.
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by Ramesh Natarajan
on July 29, 2011
Question: I installed VMWare ESXi 4.1 on a Dell Poweredge Server. I created a Virtual machine, and while installing Red Hat OS 6.1 64-bit, it gives the following error message. My server is a new Dell poweredge R710 server, which support 64-bit CPU. Why do I get this error message and How do I fix it?
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by Ramesh Natarajan
on July 27, 2011
Using Apache Virtual Host, you can run several websites on the same server.
For example, I can run both thegeekstuff.com and top5freeware.com on a single physical server that has one Apache webserver running on it.
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by Ramesh Natarajan
on July 25, 2011
Before we understand what is nginx, we should know how to pronounce nginx.
Its not N G I N X. nginx is pronounced as “Engine X”.
nginx is short form after you remove both the e’s from “Engine X”.
nginx is an open source web server that is similar to Apache, but very light weight. nginx is both web server and reverse proxy server.
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by Ramesh Natarajan
on July 22, 2011
Question: I would like to automatically rotate the apache access_log and error_log files. Can you explain with an example on how to do this?
Answer: This can be achived using logrotate utility as explained below.
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by Ramesh Natarajan
on July 20, 2011
Lazy sysadmin is the best sysadmin –Anonymous
System administrators job is not visible to other IT groups or end-users. Mostly they look at administrators and wonder why sysadmins don’t seem to have any work.
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by Ramesh Natarajan
on July 18, 2011
This article provides a total of 24 examples on iostat, vmstat, and mpstat commands.
- iostat reports CPU, disk I/O, and NFS statistics.
- vmstat reports virtual memory statistics.
- mpstat reports processors statictics.
This article is part of our ongoing Linux performance monitoring series.
Please note that iostat and vmstat are part of the sar utility. You should install sysstat package as explained in our sar (sysstat) article to get iostat and vmstat working.
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My name is Ramesh Natarajan. I will be posting instruction guides, how-to, troubleshooting tips and tricks on Linux, database, hardware, security and web. My focus is to write articles that will either teach you or help you resolve a problem. Read more about