Thursday 21 June 2018 3:00 pm

IBM report suggests that TSB testing was not rigorous enough before computer meltdown

Experts brought in to fix computer systems meltdown at TSB did not find evidence of strong enough testing of a planned migration, according to an internal report published today.

Consultants from IBM told the embattled bank’s board that it had not seen evidence of the kind of testing it would expect of the risky migration process.

The meltdown started on 22 April, when TSB had planned to complete a migration of its systems to a new system, away from a platform run by former owner Lloyds Banking Group.

The bank had attempted to move more than five million customers onto the new platform in the course of a single weekend. The failure saw hundreds of thousands of customers unable to access their accounts for weeks

“IBM has not seen evidence of the application of a rigorous set of go-live criteria to prove production readiness,” according to the report, which was created as an update to the TSB board on 29 April, four days after IBM was hired and almost a week after the first signs of problems at the bank.

IBM would expect “world class design rigour, test discipline, comprehensive operational proving” for a task of similar complexity and scale, the report said.

However, the bank’s testing before the launch may have not given enough evidence to proceed, the report suggested. Previous examples have taken place over a longer time frame, with multiple trials, and did not attempt to migrate the entire customer base simultaneously.

The report said: “Performance testing did not provide the required evidence of capacity and the lack of active-active test environments have materialised risk due to issues with global load balancing (GLB) across data centres.”

The bank’s systems are now fully operational on the new platform, a spokesperson said.

A TSB spokesperson said: “The IBM document contained a preliminary work plan with very early hypotheses based on observations to date, that were produced after only three days of engagement with TSB. The content is therefore now very much out of date."

The spokesperson added: "The hypotheses were not final, nor were they a validated view of what went wrong or of the actions that have subsequently been taken. Without this context, this document could be misinterpreted to the detriment of TSB’s customers.”

The slides were published today by the Treasury Select Committee, which has previously called for Paul Pester to be removed as chief executive of the bank after the boss of the Financial Conduct Authority, Andrew Bailey, criticised his communication with MPs for being over-optimistic.