"The first node failed because of a hardware failure at 5am yesterday morning and unfortunately the second node didn't take over when the first failed and we think that was a data corruption which was caused by the failure of the first unit."
She said staff worked through the night to get the website back up and running.
Ms Bridges was confident the website could deal with massive traffic during weather events.
"I think the main thing is the website itself was really robust - when we relaunched it last year we had a complete rebuild of the back-end. At the end of May we had something like 343,000 hits in one day and it held up to that fine - which is the whole reason for the rebuild."
The website was back up and running by about 10am today.
- nzherald.co.nz