Re:I build High Availability Platforms so Cloud is not for me
by rdl on Monday July 02, 2012 @10:02AM
(#4188887)
The problem is AWS makes representations about how available certain components will be, and the independence of various features like AZs, which turn out to be lies in practice. When a higher level system builds on top of AWS and relies on these representations, the higher level system fails.
Carriers lie about route diversity on specifically ordered diverse circuits all the time. I rarely physically trace every power cable in a colo to make sure A and B are independently fed; if someone has done it correctly 30 times before, 31 is probably going to be ok. If it is critical, or something which might be difficult, I may check, but since I am confident it will pass, I'll bundle a bunch of checks together so it only passes if all the checks pass.
Carriers lie about route diversity on specifically ordered diverse circuits all the time. I rarely physically trace every power cable in a colo to make sure A and B are independently fed; if someone has done it correctly 30 times before, 31 is probably going to be ok. If it is critical, or something which might be difficult, I may check, but since I am confident it will pass, I'll bundle a bunch of checks together so it only passes if all the checks pass.