Going MirrorBrain, seeking Mirrors

Once upon a Time…

When the Qt sources were first released on ftp.troll.no, the Troll Tech (mind the spelling, it’s that long ago!) FTP server, many FTP mirror admins quickly started mirroring the software, because it was cool, and useful to them or their company/university. And quite right so, because this meant that everyone in the world could use his local mirror to get their files real fast, i.e. high speed and low latency. However, over time, traditional mirrors were replaced by Content Delivery Networks (CDNs). They were deemed more convenient because, well, the user doesn’t need to look for the his closest mirror. The CDN is a one-stop-shop which will automatically find a fast download location. This can either be done by employing GeoIP, or by performing a distance calculation based on routing information (the users’ ASN). There are even more ways of doing this, but let’s not digress:

During the time at Nokia, the Qt packages were also moved to a Commercial CDN. It was good, but it was also expensive. As an Open Source project, we should use our resources cost-effectively and have an infrastructure that is decentralized to a certain degree. Fortunately there is a software that helps us doing that, by combining the ease of CDN-like user-experience with the old system of FTP and HTTP mirrors, and it’s called MirrorBrain. Happy users include LibreOffice, openSUSE and the KDE Project. MirrorBrain presents itself to the user as one page, redirecting the actual downloads to mirrors. While doing that it makes sure that only those mirrors that contain the latest, up-to-date version of the files will be used.

A Call for Mirrors

Since a few days, we have a MirrorBrain infrastructure in place. If you run a mirror or have a reliable, well-connected machine (>= 50 MBit/s) that can help us delivering Qt (currently a total of 120GB), please read the mirroring instructions on the Qt Project page, send us a mail and join the mirrors mailing list.

Credit where Credit is due

The KDE Sysadmin team has helped us a lot in getting MirrorBrain started while setting up the evaluation system. Peter Poeml, the uberbrain behind MirrorBrain, has been of great assistance. Finally, Digia has been sponsoring the man power to set up the production system.