Re^3: Code Conflation: Considered Harmful?

[sandfly]

Zero points of failure?

I think you're decrementing when you should be incrementing. The question is: what's the minimum number of components that need to fail for the system to fail? You're saying that for Oracle RAC, it's one. I'm not clear what you're claiming for the MySQL cluster, but obviously if every CPU in the cluster burned out, that would do it, so there is an upper bound.

[dragonchild]

Zero single points of failure. Oracle RAC depends on a central storage area. So, if that storage area fails, the database is down, even if all the processing nodes are still up. (Obviously, you can make the storage area itself redundant with various strategies. But, that's an additional step that needs to be taken.)

With NDB clustering, every processing node is also a storage node. So, the failure of any single point will not bring the database down.

Every article I've ever read on the concept of clustering says that this is the most robust architectural model.