PUBLIC MARKS from camel with tags debian & configuration

Il y a quelques temps déjà, un nouveau site web pour OBM (www.obm.org) a été mis en ligne, afin de présenter ce logiciel qui permet à ses utilisateurs de stocker, organiser et partager rendez-vous, contacts, courriels, liens, documents et des modules complémentaires de type gestion de projet/planning. Ce fut pour nous une volonté de faire partager ce projet pour lequel la communication n'était pas à son maximum. Depuis nous l'enrichissons afin de partager nos connaissances et de faire de ce Groupware une véritable alternative aux solutions propriétaires. L'un des avantages d'OBM est l'utilisation d'autres logiciels libres pour assurer les différents services d'un goupware (Cyrus, Apache, Postfix...). Cependant, pour les non-initiés, cet avantage se transforme souvent en plusieurs semaines de galère pour réussir à installer un OBM complet. OBM nécessite une certaine expertise dans beaucoup de services associés à OBM (Cyrus, Postfix, MySQL ou PostgreSQL, Java/Tomcat...). Il y a plus de 6 mois, nous avons travaillé avec des développeurs Ubuntu (et nous continuons toujours) pour publier dans Ubuntu Hardy (et maintenant Intrepid) une version packagée d'OBM. Nous nous sommes vite rendu compte qu'inclure un tel logiciel dans une distribution est pour l'instant infaisable. Pouvoir remplacer un fichier de configuration d'un service par celui dont a besoin OBM, n'est pas simplement faisable, voire impossible pour certains services. C'est pour cela que dans Ubuntu il n'y a que la partie "web" qui est pour l'instant intégrée. Nous avons quand même développé tous les autres paquets des services qui gravitent autour d'OBM. Nous espérons intégrer au fur et à mesure tous les paquets d'OBM, quand cela sera possible. Nous sommes donc heureux de vous annoncer la mise en place d'un dépôt Debian (Etch) pour une installation complète et vraiment complète d'OBM. La version disponible est la dernière version stable, la 2.1.11. Il faut souligner que ces paquets sont conçus pour un serveur dédié à OBM. Nous espérerons que grâce à ces paquets vous serez nombreux à installer et utiliser OBM : deb http://deb.obm.org etch obm À vos claviers ! Il est temps d'installer un OBM, en quelques minutes ! Voir ci-dessous pour faire vos retours et tester aussi MiniG, une version alpha d'un nouveau webmail.

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.

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.

I know it's difficult to find good documentation to configure apache2 with mod_fastcgi and suexec to make php websites works. This configuration works well with Debian Etch (4.0). Here an example of configuration.

sortie de la version 4.3 de Damn Small Linux. C’est une distribution très légère de 50Mo environ basée sur Knoppix, Debian et GNU Linux. Elle peut s’intaller sur : * Une clé USB, * Une carte Compact Flash via la méthode dite “Frugal Install”, * Un mini-cd, * Un ordinateur 486DX avec 16MB de RAM, * 128 Mo de mémoire RAM. Bref, une pure merveille pour les vieilles machines ou les petites configuration (les pc embarqués et les nano-ITX). A l’intérieur, des tonnes de logiciels. Et oui, avec 50 Mo vous pourrez en faire des choses.Navigateur, client Mail, suite office légére, XMMS, client FTP, AIM, ICQ, …

The idea behind the whole set-up is to get a High availability two node Cluster with redundant data. The two identical Servers are installed with Xen hypervisor and almost same configuration as Cluster nodes. The configuration and image files of Xen virtual machines are stored on drbd device for redundancy. Drbd8 and OCFS2 allows simultaneous mounting on both nodes, which is required for live migration of xen virtual machines. This Article describes Heartbeat2 Xen cluster Using Ubuntu (7.10) OS, drbd8 and OCFS2 (Ver. 1.39) File system. Although here Ubuntu is used it can be done in almost same way with Debian

This article explains how to set up a two-node load balancer in an active/passive configuration with HAProxy and heartbeat on Debian Etch. The load balancer sits between the user and two (or more) backend Apache web servers that hold the same content. Not only does the load balancer distribute the requests to the two backend Apache servers, it also checks the health of the backend servers. If one of them is down, all requests will automatically be redirected to the remaining backend server. In addition to that, the two load balancer nodes monitor each other using heartbeat, and if the master fails, the slave becomes the master, which means the users will not notice any disruption of the service. HAProxy is session-aware, which means you can use it with any web application that makes use of sessions (such as forums, shopping carts, etc.). From the HAProxy web site: "HAProxy is a free, very fast and reliable solution offering high availability, load balancing, and proxying for TCP and HTTP-based applications. It is particularly suited for web sites crawling under very high loads while needing persistence or Layer7 processing. Supporting tens of thousands of connections is clearly realistic with todays hardware. Its mode of operation makes its integration into existing architectures very easy and riskless, while still offering the possibility not to expose fragile web servers to the Net."

This article explains how to set up a two-node load balancer in an active/passive configuration with Pound and keepalived on Debian Etch. The load balancer sits between the user and two (or more) backend Apache web servers that hold the same content. Not only does the load balancer distribute the requests to the two backend Apache servers, it also checks the health of the backend servers. If one of them is down, all requests will automatically be redirected to the remaining backend server. In addition to that, the two load balancer nodes monitor each other using keepalived, and if the master fails, the slave becomes the master, which means the users will not notice any disruption of the service. Pound is session-aware, which means you can use it with any web application that makes use of sessions (such as forums, shopping carts, etc.).

Using NTP is a great way to keep your system clock set correctly. It works by contacting a number of servers around the world, asking them for the time and then calculating what the correct local time is from their responses.