The outage that left over 16 million Chase bank customers unable to access their online accounts last week was caused by corruption in an Oracle database, according to analyst Curt Monash.
The Chase Web site went down late last Monday evening, forcing the bank to put up a holding page indicating that the downtime was due to "scheduled maintenance". It then fell over again on Wednesday.
A spokesman told the New York Times that the fault was caused by third-party database software that corrupted information in its systems and prevented users from logging on.
In a blog, Monash says he has been contacted by someone claiming to be "a credible source close to the situation" who has laid the blame at Oracle's door. Initially, suspicion focused on storage provider EMC and its SAN controller but this has now been cleared.
According to the source, the corrupted Oracle database stored user profiles, and applications that went down include the main JPMorgan Chase portal, the bank's ability to use the ACH, loan applications and private client trading portfolio access.
The problem left $132 million in ACH transfers delayed and around 1000 auto loan and another 1000 student loan applications were lost.
Monash also claims that JPMorgan Chase was already looking at replacing Oracle, with IBM's DB2 in the frame.