We created clear plastic covers to cover empty spots on the server rack to make sure no cold air travels without going through servers. We found this to be very effective way to utilize as close to 100% of cool air.
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Tetsuro Watanabe 
田仲なお美 
さち 
神谷保険 
ClockLink 
橋本諭弥 
Seattle Execs. 
カワシマヒロキ（ひーさん） 
錦糸町の天使 
さわ