A power outage at "Europe’s largest purpose-built data centre”, Global Switch 2 – which knocked one customer offline for two days – has been blamed on a high voltage fault.
All customers lost access to services based in the GS2 data centre on Saturday 10 September, according to an interim incident report issued by hosting provider Claranet today and seen by The Register.
The outage lasted for 222 milliseconds. However, it appears it took Claranet two days to restore services.
The report said the HV fault was within the HV cable end box of the output circuit breaker for one of the on-site diesel rotary uninterruptible power supply devices.
"This caused an interruption to power for the supply feeding services within the Claranet Suite within the Global Switch 2 Data Centre."
It added: "All components damaged by the HV fault have been replaced prior to normal power operations being restored. The cable terminations of the remaining available DRUPS have been checked for integrity to ensure the same issue is not manifesting in other areas of the Global Switch 2 Power system."
The incident is the second outage to occur at GS2 in three months. In June, a lightning strike was thought to be responsible for triggering an outage. That lasted for 300ms but subsequently knocked Claranet offline for several hours.
One customer described the incidents as "unacceptable".
According to GS2, its London East data centre is designed and built to an enhanced Tier III specification, and delivers 46MVA of power and cooling.
Its spiel reads: "With diverse feeds from the National Grid's 132kV network the incoming electrical supply is considered to be one of the most resilient available to any infrastructure within the UK. London East sits at the heart of the connectivity-rich Docklands, giving you direct access to an abundance of global networks to meet both your commercial and geographical requirements."
The Register asked GS2 what measures it will put in place to prevent a similar incident happening again. The company did not answer that specific question.
However, it provided the following statement from John Stevenson, its managing director London:
Global Switch London operates its data centre campus at the very highest internationally recognised standards for reliability.
Whilst operated to exceed Uptime Institute Tier III standards, the performance for this campus has exceeded Tier IV. Incidents of this nature are extremely rare. The Global Switch infrastructure protected supplies, but one of the four power stations experienced a 222 millisecond switching event.
Throughout the weekend we sought to keep our customers fully informed at all times.
Claranet said: "Power in GS2 was cut just before 11.00am and we immediately began our assessment to ensure the facility was safe and that power supplies were reliable, before powering up hardware and other services in a controlled manner. This was completed by 1.30pm and by 5.10pm, 85 per cent of customer services had been restored.”
“Claranet’s suite at GS2 is fed by multiple power feeds from GS2’s central power system.” ®