> So, how about implementing automatic promotion of slaves to master > status, so that single-master environments can be made highly > available? This is a generic problem, and applies to both FDS and OL. > Do you think it's a good idea or not? I say bad idea. Implementing a promotion mechanism that can be relied upon turns out to be hard, possibly as hard or harder than MMR. And you end up with all the consistency issues of MMR anyway. Best to bite the bullet and implement MMR. Thankfully this was done many years ago and we can reap the rewards today. If the goal is to acheive tight consistency then simply do not use a Directory Service : use a RDBMS or some other thing that is designed to deliver it.
