"A significant amount of work has been undertaken over the Christmas break as we continue efforts to restore our services," the ATO said on January 3. "The performance of our core services such as the website and portals continue to improve and we are bringing other functions and tools back online every day.
"The complexity of the restoration means there is more work to be done to return our services to normal. There may be some disruptions to service as this work is undertaken.
"All of our external facing client systems and portals have been restored and are operational. We do not anticipate any further outages in the short term," it said.
The hardware failure that set off the outage of the ATO's systems struck on December 12, when storage hardware that had been upgraded in November 2015 by HPE experienced a failure, which in turn, was compounded by the subsequent failure of the ATO's back-up systems.
The technical issues took out some of the ATO's core internal systems and public-facing services for days. On December 16, four days after trouble first struck, Jordan referred to the issues as the "worst unplanned system outage in recent memory".
"This was an extremely unusual and unfortunate event with the outage caused by a significant and unprecedented failure of storage hardware," he said at the time.
One of the first things the ATO did following the hardware issues was to engage its service provider, HPE, to help address the outage. This makes sense, given that the outages were reportedly caused by the failure of new HPE 3Par storage units.
"A team of Hewlett Packard Enterprise (HPE) engineers continue to work closely with the [ATO] to help restore all systems to functionality as soon as possible," HPE said following the incident.
"HPE is completely committed to helping to resolve the system issues which have impacted the ATO's online services, portals and website," it said.
Source: ARN AU
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