This code used to live in Subversion so far, hosted on mirrorbrain.org. Maybe it's time to experiment with moving to GitHub. poeml, Mon 11 May 2015 23:06:47 CEST

MirrorBrain is an open source framework to run a content delivery network using mirror servers. It solves a challenge that many popular open source projects face - a flood of download requests, often magnitudes more than any single site could practically handle.

The central (and probably the most obvious) part is a "download redirector" which automatically redirects requests from web browsers or download programs to a mirror server near them.

One example of a running instance is http://download.opensuse.org/

For clients (users):

• allows to have one central URL for clients to download content
• uses geolocation and global routing data to find the closest mirror for clients
• automatically keeps cryptohashes of all files and can serve these on request
• optionally generates Metalinks (RFC5854) and Torrents in realtime
• provides automatically generated mirror list for overview (For example: https://mirrors.opensuse.org/)
• Allows to list available mirrors for single files to choose (example)

For mirrors:

• load-balancing of mirrors, based on weighting
• ability to limit requests for a mirror to its own network or country
• file level granularity (mirrors don't have to mirror the full file tree - they can choose what they want)
• reliably assess large file support of mirrors

For admins of a MirrorBrain server:

• has proven to handle hundreds of requests per second
• ability to NOT redirect certain requests, for security reasons
• content on mirrors can be protected by URL signing (clients can only download from mirrors if they successfully authenticated with the MirrorBrain server)
• commandline tools and Python module for maintenance tasks
• support for running behind a load balancer, using e.g. X-Forwarded-for header for the clients IP address
• integrated in Apaches module API, for compatibility with numerous other existing Apache modules, e.g. SSL
• multiple instances are supported to run in one Apache (one per virtual host)
• flexible logging
• more than a redirector
  • serve automatically generated cryptohashes (MD5, SHA1, SHA256)
  • generation of RFC5854 Metalinks
  • support for RFC3230 - Instance Digests in HTTP
  • support for RFC6249 - Metalink/HTTP: Mirrors and Hashes
  • generation of Torrents (including the closest mirrors as seeds)
  • support for zsync
  • support for native Yum mirror lists, compatible to Fedora and CentOS