Last Thursday sure was a weird day for the Internet in Australia. For about 45 minutes, connections to Australia’s largest ISP went down – with some involvement by Dodo – and as you’d expect, lots of people noticed. Especially when ISPs like iiNet and services like internet banking were affected. Telstra issued several statements to Gizmodo as events unfolded, and have now provided what will likely be their definitive statement on the matter.
On Thursday, 23 February between 1:41pm and 2:25pm - a 44 minute period - Telstra customers nationally were unable to access internet sites online or via a mobile phone. This affected all Telstra Internet customers and a number of related BigPond, Online and other services.
Investigations at this stage indicate the cause of the issue was due to the interaction between the configuration of a Telstra Wholesale customer network and the Telstra’s core network.
At this stage, we understand the Telstra Wholesale customer’s network began to present an excessive number of IP routes, and the configuration of Telstra’s core network (Telstra Internet Direct) allowed this to overload the Telstra network. Service was restored by removing the impact of excessive routes.
Steps were taken to add additional protection to our core network (Telstra Internet Direct). A full review of Telstra’s network protection mechanisms is being undertaken.