NANOG - the art of running a network and discussing common operational issues

Published on by Martin J Levy.

The North American Network Operators Group (NANOG) is the loci of modern Internet innovation and the day-to-day cumulative network-operational knowledge of thousands and thousands of network engineers. NANOG itself is a non-profit membership organization; but you don’t need to be a member in order to attend the conference or

Path MTU discovery in practice

Published on by Marek Majkowski.

Last week, a very small number of our users who are using IP tunnels (primarily tunneling IPv6 over IPv4) were unable to access our services because a networking change broke "path MTU discovery" on our servers. In this article, I'll explain what path MTU discovery is, how we broke it,

Route leak incident on October 2, 2014

Published on by John Graham-Cumming.

Today, CloudFlare suffered downtime which caused customers’ sites to be inaccessible in certain parts of the world. We take the availability of our customers’ web properties very seriously. Incidents like this get the absolute highest priority, attention, and follow up. The pain felt by our customers is also felt deeply

How Syria Turned Off the Internet

Published on by Matthew Prince.

Today, 29 November 2012, between 1026 and 1028 (UTC), all traffic from Syria to the rest of the Internet stopped. At CloudFlare, we witnessed the drop off. We've spent the morning studying the situation to understand what happened. The following graph shows the last several days of traffic