The Australian Taxation Office (ATO) took its website offline late Friday, following a Twitter post on Tuesday notifying users it was undertaking maintenance.
"Key online services (incl. portals & myTax) will be unavailable from 11.30pm AEDT Fri 23 Mar to 7am AEDT Mon 26 Mar while we carry out routine maintenance," the tweet reads, suggesting affected users visit the ATO maintenance page for further information.
Although the maintenance was meant to end on Monday, the ATO took to Twitter again on Friday afternoon to inform users its services would in fact be available over the weekend.
"UPDATE: Our systems will now be available this weekend. Check our system maintenance page for details and upcoming maintenance dates," it said.
However, the link provided by the taxation office returned a "Page not found" message and despite claiming availability, ato.gov.au was still offline at 11.59pm AEDT Saturday.
The maintenance was for the ATO Publication Ordering Service (PODS), despite impacting its main ato.gov.au website.
By Sunday morning, the services were up and running with no further communication provided by the government organisation.
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The outage followed a run of issues that have been plaguing the taxation office since late 2016, including "one-of-a-kind" SAN outages, and although the ATO said issues were rectified, further service disruptions ensued.
The government department had to turn its mainframe off and switch it back on again last July when a disruption occurred five days into the new financial year.
The department responded with promises of "smooth operating" IT, as well as the assurance of a more "connected and bulletproof" system than ever before.
Addressing the Finance and Public Administration References Committee on Friday, the ATO's CIO Ramez Katf discussed the outages, revealing his office is still unsure whether the cables identified as a main element causing the initial SAN outage were defective or incorrectly installed, with a final report from Hewlett-Packard Enterprise -- now DXC Technology -- yet to be published.
Katf and CDO John Dardo told the committee looking into the digital delivery of government services that penalties had been imposed on DXC Technology for allowing the SAN outage to occur in its datacentre, but confirmed Leidos, contracted by the ATO to deliver end-user computing, was not penalised.
The same committee a week prior heard from Ian Brightwell, who was previously CIO of the New South Wales Electoral Commission for 17 years.
During his probe, Brightwell revealed that in 2017, the Australian government pulled 54 websites down for an entire weekend, without providing a duplicate or interim website for citizens.
"On the 6th of May 2017, 54 commonwealth government websites were taken down for maintenance for a whole weekend," he said.
"It seems the agencies responsible for these websites did not see fit to take such precautions and took the ABN Lookup and 53 other sites offline for two days.
"This is not something Facebook would do, so why would the government agencies do it if the government has standard to encourage everyone to use digital services?"
Brightwell explained that maintenance and pulling down websites aren't synonymous.
"Don't equate maintenance with taking down websites," Brightwell said. "Websites like this, normal practice, acceptable practice ... [at the electoral commission] we had hot sites -- if one went down, the other one was there and up within a minute or two -- this should be normal practice."
He said the secondary websites should be hosted elsewhere, so if for example Sydney goes down, Melbourne can take over straight away.
No further information on the outage has been provided by the ATO.
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