[ Thanks to Paul
Shread for this link. ]
“We’ve all probably heard more than we want to hear
about clouds this week, thanks to EMC World, but there are some
things you need to think about if you’re considering adopting a
cloud model as part of your storage networking architecture.“Clouds have a place in data storage architecture planning, as
do applications that might use clouds, such as Hadoop. The standard
cloud method of data replication is to use low-cost hardware. By
replicating the data in the event of failure, the theory is that
you have data reliability. As most of the work I do is in large
storage environments, and given what I know about drive failure
rates, I have some huge misgivings about using this method to
manage petabytes of data that need to be highly reliable.“So what I want to do is take you through a step-by-step
analysis of the low-cost hardware used in most clouds. I did not
look at the failure rates of the blade, just the storage. As part
of this analysis, I went to the Web sites of all the major disk
manufacturers and used the best values across all vendors, so my
analysis is likely best case and your mileage may vary. Let’s go
through this thought process step-by-step.”