PUBLIC MARKS with tags server & debian

MySQLTuner is a script written in Perl that will assist you with your MySQL configuration and make recommendations for increased performance and stability. Within seconds, it will display statistics about your MySQL installation and the areas where it can be improved. It’s key to remember that MySQLTuner is a script which can assist you with your server, but it is not the solution to a badly performing MySQL server. The best performance gains come from a thorough review of the queries sent to the server, and an evaluation of the MySQL server itself. A qualified developer in your application’s programming or scripting language should be able to work with a MySQL database administrator to find improvements for your server. Once the server and application are optimized well, you may need to consider hardware upgrades to the physical server itself. This is a really useful tool for helping to optimize MySQL performance.Understanding the various my.cnf variables and how they affect performance can seem really complicated but this tool takes some of the pain away and makes it easier to understand the effects of each variable.It is especially useful to be able to see the global memory usage, memory usage per thread and the maximum possible memory usage - that is really valuable information that is otherwise complex to calculate.

I have tried to run both Debian Etch and Ubuntu 8.04 Server on the cluster nodes, in Dom0. I started my tests with Debian, but I had some issues with slow samba performance in one VM that I couldn't fix so I decided to try Ubuntu Server, for the first time. Both installation went OK, the main difference was that I used mainly source code in Debian, but only packages in Ubuntu. I actually ran into more problems with Ubuntu due to some early bugs in the 8.04 release, will describe them below as I go along. And I have still to prove that running this setup in Ubuntu is stable.

This article explains how you can install and configure apache2-mpm-peruser on a Debian Etch server. apache2-mpm-peruser is an MPM (Multi-Processing Module) for the Apache 2 web server, very similar to apache2-mpm-itk, but faster (almost as fast as apache2-mpm-prefork). mpm-peruser allows you to run each of your vhosts under a separate UID and GID - in short, the scripts and configuration files for one vhost no longer have to be readable for all the other vhosts. It is based on metuxmpm, a working implementation of the perchild MPM. The result is a sane and secure web server environment for your users, without kludges like PHP's safe_mode.

First and foremost, be prepared to have some patience when trying to get a USB cam to work under Linux. In trying to get mine to work, I searched many a newsgroup thread only to find there was only one message in the thread, the original question stating the problem. i.e. no one had an answer for the person who posted the question so you may be on your own trying to get your cam to work. Often times the same camera model will use different drivers for different sub-models (ex: not all QuickCam Express sub-models use the same driver). However, my trials and tribulations were a good learning experience and I'll share what I learned here to hopefully make your setup easier.

The Server is the computer you want to connect to. This is the computer where the FreeNX server will need to be installed. The name of the Ubuntu package providing the server is “freenx”. For the example used here, the home computer is the server. The Client is the computer from which you want to be able to access the Server. The name of the Ubuntu package providing the client is “nxclient”. For the example used here, the work computer is the client.

This guide explains how to set up mod_geoip with Apache2 on a Debian Etch system. mod_geoip looks up the IP address of the client end user. This allows you to redirect or block users based on their country. You can also use this technology for your OpenX (formerly known as OpenAds or phpAdsNew) ad server to allow geo targeting.

djbdns is a very secure suite of DNS tools that consists out of multiple parts: dnscache, a DNS cache that can be used in /etc/resolv.conf instead of your ISP's name servers and that tries to sort out wrong (malicious) DNS answers; axfrdns, a service that runs on the master DNS server and to which the slaves connect for zone transfers; and tinydns, the actual DNS server, a very secure replacement for BIND.

Lighttpd is a secure, fast, standards-compliant web server designed for speed-critical environments. This tutorial shows how you can install Lighttpd on a Debian Etch server with PHP5 support (through FastCGI) and MySQL support.

Lighttpd, sometimes pronounced "Lighty", is a lightweight HTTP server that can help alleviate Apache's load by serving static content. Since Lighttpd uses less resources per request than Apache, it generally serves most static content faster than Apache. This tutorial shows how to install Lighttpd behind Apache via Apache´s proxy module.

djbdns is a very secure suite of DNS tools that consists out of multiple parts: dnscache, a DNS cache that can be used in /etc/resolv.conf instead of your ISP's name servers and that tries to sort out wrong (malicious) DNS answers; axfrdns, a service that runs on the master DNS server and to which the slaves connect for zone transfers; and tinydns, the actual DNS server, a very secure replacement for BIND.

This short guide describes how to install Windows XP or Windows 2003 Server on Xen. It provides an overview of the Debian Linux Etch installation, and detailed steps for installing and configuring Xen and starting the Windows XP or Windows 2003 Server installation.

If you have a server with more than 4GB RAM and want to install a 32bit Debian Etch on it (following this tutorial: Debian Etch And Xen From The Debian Repository), you'd expect the Xen-PAE kernel to see all your RAM because the Xen-PAE kernel supports up to 64GB RAM. In fact, it recognizes only about 3.3GB RAM due to a bug in the GRUB bootloader. This article explains how you can fix GRUB so that all your RAM gets recognized. I do not issue any guarantee that this will work for you!

Ever had to make the same change on more than one Linux/unix server? Find it annoyingly painful to keep repeating the exact same commands again and again and again? This tool addresses exactly this problem. You run a utility (cssh) providing a number of server names as parameters, and then xterms opens up to each server with an extra “console” window. Anything typed into the console is replicated into each server window (so, for examples, you can edit the same file on N machines at the same time, or run the same commands with the same parameters across those servers). It is also possible to type into the server windows directly, or temporarily disable replication to one or more of the servers through the “Hosts” menu.

The eBox platform will effectively and easily help you managing the advanced services for your corporate network. Designed with extensibility in mind it offers, among others, these modules: Firewall, Transparent proxy, Traffic shaping, VPN’s, Content filter, NTP Server, Users and groups, Mail server… more modules!

This guide describes how to set up a full email solution in Debian Linux (all code is from Debian Etch). I was asked to design a secure, scalable, portable solution for a small company. While the guide references many 'servers', the company only had 4 physical machines, Xen was used to virtualize the entire solution. That particular aspect of the system is not discussed in this guide, although I will try to get it into the next revision.