Press & Presentations
The below is a collection of publications and presentations about MirrorBrain. Most of the material goes into quite some detail about the background of the problem which this framework solves.
Talk at FOSDEM 2010
This presentation took a funny course. I went into it with a very high-level overview about MirrorBrain and the firm intention to keep it free of techical details. (PDF available.) Surprisingly, the audience largely consisted of people who were both interested in details of MirrorBrain's inner workings and had specific technical questions. So the talk quickly turned into a lively discussion about specific challenges of running a mirror infrastructure, and the possible approaches. It was a great and unique opportunity to have these people together in one room. I'm looking forward to build upon these contacts, and hope to see further discussion on the mailing list. Video available here and on YouTube.
Interview about MirrorBrain
Dinar Valeev, openSUSE community member, asked me questions about MirrorBrain.
Talk at FOSDEM 2009
This talk was held at FOSDEM 2009 in Brussels. The topic was a rationale why more collaboration between content providers and mirror operators would be highly useful. The talk leaves technical matters in the background and rather attempts to make the big picture visible. It is sort of a vision of a Free Content Delivery Network for Free Software that we could build. Video (230 MB, ogg format) here, and slides available as PDF for a quick dive. A video at blip.tv exist here.
Article (German) in Linux Magazin
Talk at openSUSE Knowledge Sharing, 2008
It includes some live demos, showing two metalink clients (aria2c and DownThemAll) in action.
Talk at ApacheCon EU 2008
The following is from a talk held at ApacheCon EU 08 about the MirrorBrain, called "Scaling Your Download Infrastructure With Your Success". Available as PDF.
When an organization offers files for download, and grows public, infrastructure might need to serve more requests than the single organization can technically handle. One option to scale is using paid services of a content delivery network (CDN). This is often not affordable, especially for Open Source projects. Another way is building up a mirror infrastructore. But choosing an appropriate mirror is often left to the user, and mirrors might be out of date, incomplete, or unreliable.
This talk shows how to build a poor man's CDN, using plain mirror servers and a redirecting Apache HTTP server. On the example of download.openSUSE.org, it shows how mirrored content can be transparently integrated into the web service, and how requests are redirected to geographically close mirrors using IP geolocation. The demonstrated infrastructure comprises means to scan mirrors and keeping track of present files in a MySQL database, active monitoring of mirrors, and mod_zrkadlo, a redirecting Apache module built upon the DBD framework.
Along the way, the talk discusses different approaches in geographical redirection of bulk data, load sharing with weighted randomization, high availibility and scaling issues, mirror stickiness, and client side robustness. Also discussed are problems that have been encountered in real life, solutions and open questions.