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I have been experimenting with NAGIOS3 on Ubuntu (I will write a how-to-install on NAGIOS later) and it has served me very good in monitoring my 7 VPS from different providers in different part of the world. I have already recorded 3 hours of downtime from ThrustVPS which is a great deal for me. I now know which VPS has the best time and which ones have hiccups (e.g. my 2Host VPS gave me two unreachable notifications but the VPS was running and still reports the uptime as 4 days).

Since I use twitter more, even when Im on the road, notifications via email is a bit slow for me. Luckily I found a great tutorial online to do that.

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If you are not getting a package on Ubuntu, please check to see if your /etc/apt/sources.list file is updated. This is common with most VPS providers

On VPS, especially with challenging small memory limit (e.g. 64MB or 128MB) lighttpd is the best option instead of Apache. In this article I will show you how to do that. On a fresh box (which has no apache installed) type this to get lighttpd webserver installed

apt-get install lighttpd

Now install PHP5 CGI package and PHP5 command line package

apt-get install php5-cgi php5-cli

Edit the following file

nano /etc/php5/cgi/php.ini

and uncomment this line

cgi.fix_pathinfo = 1

Now enable fastcgi module

lighty-enable-mod fastcgi

Restart Lighttpd

/etc/init.d/lighttpd restart

You get the welcome page

Lets install MySQL 5.1 server and client

apt-get install mysql-server mysql-client

and optionally phpMyAdmin

apt-get install phpmyadmin

Now create a test page to see if phpinfo is all Ok

nano /var/www/info.php

Type in the following

<?php
phpinfo();

ADOdb library is a very good data abstraction layer for PHP. Installing a PHP extension enables the library to auto-detect this and give even better performance. To install this library on Ubuntu 10.04 LTS do this

apt-get install php5-adodb

I recently found out about T1LIB. But I had no clue how to install this. Lucky for me I am on Ubuntu and I have the ability to search for a package.

T1LIB is actually in the latest Ubuntu 10.04 LTS. You can install it by punching in the following command

apt-get install t1lib-bin

Are you getting these errors in Joomla?

Warning: Parameter 1 to modMainMenuHelper::buildXML() expected to be a reference, value given in /home/xx/public_html/libraries/joomla/cache/handler/callback.php on line 99

or

Warning: Parameter 1 to HTML_content::show() expected to be a reference, value given in /home/xx/public_html/travel/includes/Cache/Lite/Function.php on line 92

Its because Joomla does not support PHP 5.3 or PHP 5.3.1

Just downgrade your PHP version and these errors will go away

If you are using

yum update

on CentOS and getting the following errors

Missing Dependency: /usr/lib/python2.4 is needed by package libxml2-python-2.6.26-2.1.2.7.i386 (installed)
gamin-python-0.1.7-8.el5.i386 from installed has depsolving problems
Missing Dependency: /usr/lib/python2.4 is needed by package gamin-python-0.1.7-8.el5.i386 (installed)
Error: Missing Dependency: /usr/lib/python2.4 is needed by package libxml2-python-2.6.26-2.1.2.7.i386 (installed)
Error: Missing Dependency: /usr/lib/python2.4 is needed by package gamin-python-0.1.7-8.el5.i386 (installed)

Don’t panic, the solution is simple … just run the following command

yum clean all

Then do

yum update

If you want to install PHP 5.2.x instead of the PHP 1.5.6 offered with default CentOSPlus repo. Please consider installing the utterramblings repo. Setting up this repo is a breeze … just follow these steps

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I have seen people installing Apache, PHP and MySQL from source code on a production server. You should NEVER, NEVER, NEVER install these packages from source on an RPM or DEB based Linux distributions. Did I say “NEVER” enough times to make your realize that it is not a good practice?

Installing from source is bad idea; there are many reasons for this but the major one is that you will be spending a lot of time keeping the system updated. If you love installing from source then I would suggest using a different distribution e.g. Gentoo.

You can build from source if the package is not available in yum but still, try to use “yum” (or “apt-get” on Ubuntu) because it will save a lot of your time when upgrading your packages.

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Earlier, I posted a how-to to Install Webmin on Ubuntu, now im going through the tutorial again but this time for CentOS.

Install dependancies before we proceed to install webmin

yum -y install perl-Net-SSLeay

Download the latest version of webmin

wget http://downloads.sourceforge.net/project/webadmin/webmin/1.500/webmin-1.500-1.noarch.rpm?use_mirror=ignum

Once it is downloaded, install the RPM using the following command

rpm -i webmin-1.500-1.noarch.rpm

No more steps required. Its installed
Go to your browser and access the control panel with valid ssh credentials

Since twitterfeed.com has not been working good for me so I started looking at alternatives and found this great post about how to do this via PHP

Read RSS Feed Mashup + Twitter = Yummy!