[WALoeIII]

I wish I could upvote this 50 times.

The diagrams show two separate masters in different regions with their own slaves, yet DNS is essentially randomly delivering users to each "half". There is no mention of how this is handled, or even that you would have to consider it.

[danoprey]

Agreed, every step in this could be an article in itself, but the intention was just to give an overview of all the options.