What caused the major Telstra NBN outage and disconnected customers

Telstra customers were left with no connections after a cyber attack on their servers caused major disruptions across the eastern states of Australia.

The issues started just after 10am when customers flocked to social media to ask Telstra about any disruptions they were aware of.

Telstra soon reported there was an issue impacting connections including the NBN.

⚠️ Our team is looking into an issue impacting some home internet connections including nbn. We’ll keep you posted as we get on top of it. Sorry to mess with your Sunday plans.

— Telstra (@Telstra) August 2, 2020

An update at 11.42am identified the problem as a DDoS (Distributed Denial of Service) attack on its DNS (Domain Name Servers) which are used to route online traffic.

A DDoS is when a cyber attacker targets servers with more requests than the infrastructure can handle.

The attack is basically trying to overwhelm the server to a point where it shuts down.

🔒 Update: We’ve identified the issue and are working on it. Some of our Domain Name Servers (DNS) used to route your traffic online are experiencing a cyber attack, known as a Denial of Service (DoS). Your info isn’t at risk. We’re doing all we can to get you back online.

— Telstra (@Telstra) August 2, 2020

And by shutting down that means customers are cut off from the internet.

It’s the online equivalent of a kink in a hose that won’t allow water through.

Telstra assured customers their information was safe despite the cyber attack.

By midday Telstra said it was confident it had blocked most of the malicious traffic that was targeting its services  and were working to get services back to normal.

Telstra’s mobile network was unaffected.

By 12.30pm on August 2, 2020 Telstra were still working on the issue.

UPDATE: By 2.25PM Telstra had announced the issue had been resolved and connections were working again.

Telstra said: “The massive messaging storm that presented as a Denial of Service cyber-attack has been investigated by our security teams and we now believe that it was not malicious, but a Domain Name Server issue.”

But there was a way around the issue by changing your DNS settings from Telstra to Google.