Early investigations of a nationwide collapse of the Easynet network have pointed the finger at a software update to a Cisco router.
The outage began at 8.32am on Wednesday, and for some customers lasted most of the working day.
"An Easynet edge router crashed due to a software bug condition triggered by an invalid update from an external source into the Easynet network," a company review of the incident, seen by The Register, says.
The router was located at one of Easynet's London points-of-presence. It was isolated from the network and all traffic re-routed via another London site.
Later, overnight, and under advice from Cisco, engineers made software changes in an attempt to ensure the error cannot occur again. For Easynet and the thousands of businesses affected, the real recriminations are now beginning, however.
In a statement yesterday, the provider anticipated "full service will be restored to them well within our normal [service level agreements]". Yet subscribers to its "business grade" Surestream ADSL product were offline until after 3pm.
Easyney sells its SureStream ADSL product as an alternative to a leased line, with a 99.9 per cent uptime guarantee (quarterly). That guarantee wa easily broken for yesterday, with some customers suffering more than 6 hours downtime. ®
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