FreeBSD Turn On Process Accounting – Track System Resources Used By Users

Posted on in Categories FreeBSD, Howto, Monitoring, Security, Sys admin, Tips, Troubleshooting, Tuning last updated January 8, 2009

I’ve already written about Linux process accounting under Linux ( see how to keep a detailed audit trail of what’s being done on your Linux systems). You can easily setup process accounting under FreeBSD. This tutorial expalins how to enable and utilizing FreeBSD process accounting including many other useful options are explained to keep track of system resources used, and their allocation among users.

Leap Second To Be Added End Of 2008 And Its Impact On Clustered Computers / Network

Posted on in Categories Hardware, High performance computing, Linux, News, Sys admin, Tips, UNIX, Windows server last updated December 31, 2008

Get ready for a minute with 61 seconds. Scientists are delaying the start of 2009 by the first ‘leap second’ a timing tweak meant to make up for changes in the Earth’s rotation.

The aged Earth is slowing down in its daily rotation, at least in the current epoch. So a leap second is added (a one-second adjustment added) to our time. This year will be exactly one second longer.

Precise time measurements are needed for high-speed communications systems among other modern technologies such as clusters, GPS, networks. You need to make sure that you are running updated version of ntpd that support leap second for UNIX and Windows computers.

Apache2 mod_fastcgi: Connect to External PHP via UNIX Socket or TCP/IP Port

Posted on in Categories Apache, CentOS, fedora linux, Howto, lighttpd, Networking, php, RedHat/Fedora Linux, Security, Tips, Troubleshooting, Tuning last updated December 30, 2008

Now, mod_fastcgi is configured and running. FastCGI supports connection via UNIX sockets or TCP/IP networking. This is useful to spread load among various backends. For example, php will be severed from 192.168.1.10 and python / ruby on rails will be severed from 192.168.1.11. This is only possible with mod_fastcgi.

Red Hat / CentOS Apache 2 FastCGI PHP Configuration

Posted on in Categories Apache, CentOS, Howto, Networking, package management, php, RedHat/Fedora Linux, Security, Tips last updated December 30, 2008

FastCGI is a protocol for interfacing interactive programs with a web server. FastCGI’s main aim is to reduce the overhead associated with interfacing the web server and CGI programs, allowing a server to handle more web page requests at once.

Also, PHP is not recommended with multithreaded Apache2 (worker MPM) because of performance and some 3rd party PHP extensions are not not guaranteed thread-safe.

nginx and lighttpd has inbuilt support for FastCGI. For Apache web server you need to use either mod_fastcgi or mod_fcgid.

mod_fastcgi allows server and application processes to be restarted independently — an important consideration for busy web sites. It also facilitates per-application security policies — important for ISPs and web hosting companies.

In this quick tutorial, you will learn about Apache 2 + mod_fastcgi + PHP installation and configuration under Red Hat Enterprise Linux / CentOS Linux version 5.x+.

How To Convert From a VMware Image To Virtualbox Image

Posted on in Categories GNU/Open source, Hardware, Howto, Linux, Linux desktop, Linux distribution, Linux Virtualization, package management, Tips, vmware, Windows, windows vista last updated December 22, 2008

VirtualBox is a virtual emulator like VMWare workstation. It has many of the features VMWare has, as well as some of its own.

I really like new Opensource VirtualBox from Sun. It is light on resources. Here is a quick tip – you can convert a VMware virtual machine (image) to a VirtualBox machine (image) using qemu-img utility, without reinstalling the GUEST operating system

Upgrade WordPress 2.7 in 3 Simple Steps

Posted on in Categories GNU/Open source, Howto, Linux, Shell scripting, Sys admin, Tips, UNIX last updated August 9, 2016

Wordpress version 2.7 has been released and can be upgraded easily using UNIX / Linux shell prompt. A few assumptions:

  1. Wordpress database name: wptheosblog
  2. Wordpress directory name: /var/www/html/theos.in
  3. Wordpress domain name: theos.in
  4. Operating system: Linux
WARNING! If you are not comfortable with UNIX shell prompt (IF YOU ARE new to a UNIX/Linux os), please follow traditional way of upgrading wordpress and DO NOT use the three Steps described here.