Since the initial outage, which struck on 12 December, 2016, until early February this year, the ATO intermittently took services offline as it worked with HPE, one of its IT contractors, to replace the failed 3Par storage hardware - which had been upgraded in 2015 by HPE - and restore systems to full capacity.
The outage and the resulting efforts to rectify the technical issues subsequently prompted the ATO to engage PricewaterhouseCoopers to conduct an independent review of the incident, while HPE also undertook an internal investigation over the matter.
Earlier last year, it was IBM that was entangled in a high profile technical mishap, with the online 2016 Census project it was contracted by the Australian Bureau of Statistics (ABS) to lead, taken offline after being hit by a series of Denial of Service (DoS) attacks.
That event saw IBM representatives face questions during a parliamentary inquiry into the problems that plagued the portal on Census night.
It also saw the external IT services provider subsequently make a "very substantial financial settlement," according to Prime Minister, Malcolm Turnbull, in relation to the estimated $30 million price tag that resulted from the fallout 2016 Census debacle.
"ABS put too much faith in IBM," Turnbull said in November last year.
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