How To Set Up A Loadbalanced High-Availability Apache Cluster

This tutorial shows how to set up a two-node Apache web server cluster that provides high-availability. In front of the Apache cluster we create a load balancer that splits up incoming requests between the two Apache nodes. Because we do not want the load balancer to become another "Single Point Of Failure", we must provide high-availability for the load balancer, too. Therefore our load balancer will in fact consist out of two load balancer nodes that monitor each other using heartbeat, and if one load balancer fails, the other takes over silently.

Server Monitoring With munin And monit

In this article I will describe how to monitor your server with munin and monit. munin produces nifty little graphics about nearly every aspect of your server (load average, memory usage, CPU usage, MySQL throughput, eth0 traffic, etc.) without much configuration, whereas monit checks the availability of services like Apache, MySQL, Postfix and takes the appropriate action such as a restart if it finds a service is not behaving as expected. The combination of the two gives you full monitoring: graphics that lets you recognize current or upcoming problems (like "We need a bigger server soon, our load average is increasing rapidly."), and a watchdog that ensures the availability of the monitored services.

Mirror Your Web Site With rsync

This tutorial shows how you can mirror your web site from your main web server to a backup server that can take over if the main server fails. We use the tool rsync for this, and we make it run through a cron job that checks every x minutes if there is something to update on the mirror. Thus your backup server should usually be up to date if it has to take over.

The Perfect Setup - Fedora Core 5 (64-bit)

This is a detailed description how to set up a Fedora Core 5 based server that offers all services needed by ISPs and hosters (web server (SSL-capable), mail server (with SMTP-AUTH and TLS!), DNS server, FTP server, MySQL server, POP3/IMAP, Quota, Firewall, etc.). This tutorial is written for the 64-bit version of Fedora Core 5, but should apply to the 32-bit version with very little modifications as well.

The Perfect Setup - CentOS 4.3 (64-bit)

This is a detailed description how to set up a CentOS 4.3 based server that offers all services needed by ISPs and hosters (web server (SSL-capable), mail server (with SMTP-AUTH and TLS!), DNS server, FTP server, MySQL server, POP3/IMAP, Quota, Firewall, etc.). This tutorial is written for the 64-bit version of CentOS 4.3, but should apply to the 32-bit version with very little modifications as well.

Simple Apache 2 Tomcat 5 mod_jk Integration

The whole tutorial is based on many tutorials, but I made a very simple one, with no virtual hosts.

The main source of info can be found here:

http://www.howtoforge.com/apache2_tomcat5_mod_jk

Removing A User

Employee turnover in most organizations runs high. So unless you run a small shop with a stable user base, you need to learn how to clean up after an employee leaves. Too many so-called system administrators do not understand the stakes involved when they manage users. Disgruntled former employees can often cause significant trouble for a company by gaining access to the network.

Syncing Websites to Your Palm for Offline Reading

This is a brief tutorial on how to sync websites to your palm for offline reading. The websites are stored in Plucker format. You will need to install the Plucker viewer for palm which can be found at the Plucker website. The software you will use to grab the websites and convert them into Plucker format is called Sunrise. To transfer the Plucker files to a Palm you will need pilot-link.

DSPAM is a scalable and open-source content-based spam filter designed for multi-user enterprise systems. It's great at filtering out spam but on busy mailservers the pruning of the MySQL databases takes way too long time. This small tutorial/hack can speed up the pruning of old data considerably.