Tax office services still offline
The Australian Taxation Office's online system has been taken down by a world-first glitch in its computers.
The ATO announced its website and other online services were not working just before 9.30am AEDT on Monday.
Access to tax and super information were back online on Tuesday evening but tools, calculators and online services including portals were still down.
ATO chief information officer Steve Hamilton said the office was working with provider Hewlett Packard Enterprise to resolve the issues with its online services, portals and website.
But he said no taxpayer information had been compromised.
"Specialist engineers have been working through the night (on Monday) with ATO staff to rectify the outages," he said.
"These outages relate to a new hardware storage solution that was upgraded in November 2015. "
Mr Hamilton said the primary back-up systems that should have kicked in immediately were also affected.
"We understand this is the first time this problem has been encountered anywhere in the world and we are working with HPE to determine the underlying cause," Mr Hamilton said.
"While these investigations are ongoing, we have had to implement alternative recovery procedures that are taking longer to complete."
The ATO said it hoped to resume key services like the tax agent portal and some services on ato.gov.au later on Tuesday.
"We will work with all clients to ensure that nobody is disadvantaged as a result of these systems issues," a spokesman said.
"Alternative work arrangements have been made for those ATO staff impacted by the outage."
The ATO apologised for any inconvenience.
The fault was not caused by any external factors such as a denial of service attack, like the one that brought down the 2016 Census.
Revenue Minister Kelly O'Dwyer said the tax office had advised her the problems were being rectified.
"The ATO will undertake a full investigation of its IT systems to ascertain how this event occurred," she said.
Labor frontbencher Andrew Leigh said the government needed to explain why it was unable to provide basic online services.
"The tax office site outage is inconveniencing taxpayers and tax agents alike," he said in a statement.
"This comes just four months after the Turnbull government stuffed up the 2016 Census and wasted millions of hours of Australians' time."
Website iTnews reported the collapse of two new HPE 3PAR SAN data storage systems, installed late last year, had caused the loss of one petabyte of data.
A petabyte is the equivalent of 20 million, four-drawer filing cabinets full of text.
Tax Institute president Arthur Athanasiou told AAP the problem was affecting not just taxpayers but tax agents.
"You can't rush to judgment against the ATO without knowledge of all the facts, but if the source of the prolonged failure is because of internal issues, such as defective hardware, the ATO must be better resourced to be able to ensure such failures don't occur, given the wide dependence on ATO systems by tax professionals and taxpayers," he said.
"We hope the ATO will ensure that taxpayers and agents will not be worse off as a result of the impact of this system disruption to their business."