A major outage at Australia's largest telecommunications company has cancelled train services, left thousands without mobile coverage, and sparked an investigation into emergency calls that were not connected.
The disruption began at 04:30 local time on Wednesday and affected "some mobile calls and data services", said Telstra's chief financial officer Michael Ackland. Services were fully restored about 12 hours later. A software defect related to time-keeping servers at data centres in Sydney and Melbourne was to blame – not a cyber attack, Ackland added.
“Telstra outage halts trains and emergency calls; software defect blamed, regulator investigates.”
Australia's Prime Minister Anthony Albanese described the outage as "deeply concerning". Telstra called it "intermittent" but acknowledged the impact had been "national". Ackland said the company had conducted welfare checks on customers who had called emergency services during the outage, with six requiring immediate help. Back-up systems, which divert emergency calls through other mobile carriers, largely worked as they should, he added.
In Victoria, all regional train services were cancelled while some regional services in New South Wales were also disrupted. National freight services were affected, and payment systems went down – about 80,000 businesses using the Tyro app were hit.
Communications Minister Anika Wells said the country's telco regulator, the Australian Communication and Media Authority, will investigate the outage.
Asked if Australia could still rely on its largest mobile network, Ackland said: "Australia can absolutely have faith in its biggest telco... we take these outages very very seriously. Our investment in resilience and cyber security and redundancy in our network is significant but it is a big and complex network and from time to time, issues do occur."
The incident echoed a systems outage at Optus – the second largest telecoms company in Australia – last September, which led to three deaths after hundreds of people across more than half the country were unable to call emergency services for 13 hours. Optus was also fined after an outage in 2023 left thousands unable to call emergency services.
The exact cause of Wednesday's disruption remains unknown, but the software defect has now been identified – and the regulator's investigation will determine whether lessons from past failures have truly been learned.