Days after claiming 99.999% availability for its new cloud computing service, a US Defense Department spokesman says he misspoke and meant to say the agency is achieving 99.99% availability instead.
At issue is the stability and reliability of the Defense Department's cloud computing service, which is called RACE for Rapid Access Computing Environment.
The Defense Information Systems Agency (DISA) operates RACE using HP blade servers, VMware software and either Microsoft Windows or Red Hat Linux operating environments.
DISA charges a monthly fee to military users to run their applications on the virtual servers provided by the RACE platform.
On 3 October, DISA announced that the year-old RACE service would support production applications. Until now, RACE has been available for test and development of new applications, but not for operations.
As part of that announcement, a DISA spokesman said RACE is achieving 99.999% availability. Now this spokesman says he meant to say 99.99% availability.
"I think I stuttered midway through the sentence when we were talking about availability," admits Henry Sienkiewicz, technical program director of DISA's Computing Services and RACE Team.
"Our target performance is four nines, and we try to adhere to that using the normal processes, [service-level agreements] and the same type of reliability upon which our customers have depended in the past."
The difference between the two availability claims for RACE is significant.
A system that has so-called "five nines" of availability has 5.26 minutes of downtime in a given year, while a system with "four nines" of availability has 52.6 minutes of downtime in a given year, according to Sun.