In one of those dreaded "oopsie" moments, a mistake a Cisco this week took down the company's entire Web site for several hours.
According to the Cisco blog, "The issue occurred during preventative maintenance of one of our data centers when a human error caused an electrical overload on the systems. This caused Cisco.com and other applications to go down. Because of the severity of the overload, the redundancy measures in some of the applications and power systems were impacted as well, though the system did shut down as designed to protect the people and the equipment. As a result, no data were lost and no one was injured. Cisco has plans already in process to add additional redundancies to increase the resilience of these systems."
Emphasis was added to the above statement to point out that even with a redundant system in place that entire site still went offline. That must have been one heck of a mistake that someone made.