Optus says traffic not diverted away from firewall before upgrade

A firewall upgrade at Optus that caused Triple Zero calls to fail for 13 hours did not follow internal traffic routing guidance and processes.

CEO Stephen Rue said that the playbook for a “successful upgrade”, drawn from past experience, was not followed.

Specifically, he said that an initial step “to divert calls away from the relevant part of the core network to a separate part of the core network” did not occur.

“The issue occurred because there was a deviation from established processes,” Rue said.

After traffic is diverted, Rue said the process is to “lock” the equipment behind the firewall; “safely upgrade the firewall; with the final step being to unlock and re-divert the traffic back.”

The upgrade, which was scheduled to run across two nights, appeared to be rolled back after the Triple Zero issue was discovered.

In past press conferences, as well as today’s, Rue has said Optus was “accountable” for the work, suggesting a third-party was either involved or even performed the upgrade work.

Rue confirmed that was the case today, and that a joint team between Australia and Chennai runs the upgrades.

He declined to blame the third-party, repeating that Optus is “accountable for [its] network.”

Rue said that of the 631 customers that tried to place an emergency call, around 480 failed outright. Around 86 customers did manage to place a call through the Optus network, while 65 others managed to “camp on” to Telstra or TPG infrastructure, which carried their calls.

Rue shut down a series of questions asked about the impact that the incident might have on customer subscriber numbers or his own role.

The update coincided with Optus appointing Dr Kerry Schott to review the incident, and with an apology from Optus’ parent company Singtel.