Debian Security Host Bandwidth Saturation

September 20th, 2005

The recently released security update of XFree86 in DSA 816 for sarge and woody has caused the host security.debian.org to saturate its 100MBit/s network connection entirely. Due to the large number of X packages, the gross size of these packages and the high number of users who need to install the update, the server is busy sending out updates which exhaust its total outgoing bandwidth.

This incident happens before new a security infrastructure is in place which would have avoided this. At the moment we ask our users to accept delays in their update until the situation is relaxed again.

Yesterday morning, at about 11 o'clock (CEST, i.e. UTC +0200) the files for the security update DSA 816 (XFree86) were installed on the public security server. The result was similar to a distributed denial of service since literally thousands of users tried to fetch the updates. Since then the host saturates its network connection entirely.

Independent of this there have been discussions about restructuring the security infrastructure in order to provide a more failsafe solution, that can also deal with high bandwidth peaks better than a single machine.