Sponsorised links
April 2008
Vdoop - Manage your virtual cluster - Vdoop
by camel
Every day, search companies like Google download terabytes of data from the Internet, store it on clusters of thousands of machines, and process it so that it can be easily searched. To make this possible, these companies need sophisticated distributed file system and parallel programing architectures.
Have you ever heard of the Map/Reduce distributed parallel programing paradigm? If you are a computer scientist, you should have, because every time you submit a Google search, you are using Map/Reduce. Despite growing demand from companies like Google, Yahoo, and Microsoft, few computer science majors have even heard of Map/Reduce, let alone graduate well versed in its use. Unfortunately, several barriers exist to integrating Map/Reduce into computer science curricula. Obtaining a large cluster, configuring it, and installing complicated distributed file system and parallel programing software is difficult, time consuming, and expensive.
In the past, Google's solution to this problem has been to ship entire clusters pre-configured with Map/Reduce software to select universities. In essence, Vdoop does same thing, with exactly the same software, except for our clusters are virtual, and hence free.
Trouver à quel paquet appartient un fichier - La solution
by camel
& 1 other
(via)
Il peut arriver, par exemple quand on compile, que le système nous réclame un fichier précis.
Problème: Comment savoir dans quel paquet est disponible ce fichier ?
PHP File Upload Configuration
by camel
& 1 other
Though PHP presents a very versatile and user friendly interface for handling file uploads, the default installation is not geared for working with files in excess of 2 Mega Bytes. This article will help you configure your PHP engine for handling such large file transfers.
Sponsorised links
March 2008
jQuery File Tree
by camel
& 1 other
jQuery File Tree is a configurable, AJAX file browser plugin for jQuery. You can create a customized, fully-interactive file tree with as little as one line of JavaScript code.
TrueCrypt - drive and file encryption
by wabaus
& 36 others
Super secure drive and file encryption for Windows/Mac/Linux
February 2008
Heartbeat2 Xen cluster with drbd8 and OCFS2
by camel
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
Apsis Gmbh
by camel
& 1 other
The Pound program is a reverse proxy, load balancer and HTTPS front-end for Web server(s). Pound was developed to enable distributing the load among several Web-servers and to allow for a convenient SSL wrapper for those Web servers that do not offer it natively. Pound is distributed under the GPL - no warranty, it's free to use, copy and give away.
WHAT POUND IS:
1. a reverse-proxy: it passes requests from client browsers to one or more back-end servers.
2. a load balancer: it will distribute the requests from the client browsers among several back-end servers, while keeping session information.
3. an SSL wrapper: Pound will decrypt HTTPS requests from client browsers and pass them as plain HTTP to the back-end servers.
4. an HTTP/HTTPS sanitizer: Pound will verify requests for correctness and accept only well-formed ones.
5. a fail over-server: should a back-end server fail, Pound will take note of the fact and stop passing requests to it until it recovers.
6. a request redirector: requests may be distributed among servers according to the requested URL.
Pound is a very small program, easily audited for security problems. It can run as setuid/setgid and/or in a chroot jail. Pound does not access the hard-disk at all (except for reading the certificate file on start, if required) and should thus pose no security threat to any machine.
Rip Myspace MP3 files
by maxxyme
Quick hint to "rip" MP3 files available to stream on Myspace's profiles thanks to Firefox extension Firebug
January 2008
Heartbeat2 Xen cluster with drbd8 and OCFS2 -- Ubuntu Geek
by camel
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
Idea
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.
dlog - log file analyzer for qmail, dnscache, tinydns, rbldns, axfrdns, publicfile and qpsmtpd
by camel
A log file analyzer for qmail, dnscache, tinydns, rbldns, axfrdns, publicfile and qpsmtpd.
Three Ways To Access Linux Partitions (ext2/ext3) From Windows On Dual-Boot Systems | HowtoForge - Linux Howtos and Tutorials
by camel
If you have a dual-boot Windows/Linux system, you probably know this problem: you can access files from your Windows installation while you are in Linux, but not the other way round. This tutorial shows three ways how you can access your Linux partitions (with ext2 or ext3 filesystem) from within Windows: Explore2fs, DiskInternals Linux Reader, and the Ext2 Installable File System For Windows. While the first two provide read-only access, the Ext2 Installable File System For Windows can be used for read and write operations.
Using multiple network cards in XEN 3.0
by camel
Xen is great. But installing more than one network card became a pain when I tried it the first time. There are some documents describing the principle but I was unable to find a real life example somewhere else. So this is a summary about how it works here now.
Using a bridge for a Dom is generally a good idea but then all packets traversing the bridge can be intercepted by any Dom that is using the same bridge. Having a single network card in a Xen landscape also means that theoretically each Dom would be able to sniff all packets traversing this single network card including packets to and from other Doms. A solution is to have more than one network card attached to Xen using a single network card for a single dom.
The scenario described here has a server with 3 network cards installed. The first card should be used to access Dom0 and some other DomNs while the second and third network card should be used to purely access Dom1 rsp. Dom2. The Dom configuration file just needs to select the appropriate bridge for each dom.
Access to Ext2/Ext3 from Windows XP
by camel
How to get safe and quick access to alternative file systems? DiskInternals Linux Reader is a new easy way to do this. This program plays the role of a bridge between your Windows and Ext2/Ext3 Linux file systems. This easy-to-use tool runs under Windows and allows you to browse Ext2/Ext3 Linux file systems and extract files from there.
December 2007
November 2007
ssh on multiple servers Using cluster ssh -- Debian Admin
by camel
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.
Apache Synapse 1.1 - gridvm.org
by camel
Apache Synapse offers a wide range of connectivity, including HTTP/S, JMS, (S)FTP, SOAP, WS-ReliableMessaging and WS-Security. The project has been designed to allow administrators to support advanced functionality such as load-balancing, throttling, and failover without writing code.
The new Apache Synapse 1.1 release includes many enhancements based on feedback from users, including
* Apache VFS based file transport - supports File System, FTP, SFTP, JAR, ZIP, TAR, GZIP, Mime
* Scheduled Task support makes it simple to run repetitive tasks
* XQuery mediator - simplifies XML transformation with the XQuery standard
* POJO Command mediator - allows the creation of message-independent mediation logic
* DB Report and DB Lookup mediators - support message augmentation and database logging
* Cache and Throttle mediators/enhancements - improve performance and manage load on existing services
* Split/Clone/Aggregate mediators - support batch processing of large messages
* Improved logging and tracing support
With asynchronous support for HTTP and HTTPS, Apache Synapse has very high scalability under load, supporting thousands of concurrent connections even with limited threads. Combined with streaming XML support, Apache Synapse has class-leading performance results.
The Apache Synapse code and binaries are available from the website at http://ws.apache.org/synapse
