Multi-Master MySQL

Implementing multi-master setups with MySQL is fairly trivial in basic terms, but for an effective environment much more is involved. There are some tools (such as MMM, Multi-Master MySQL Manager) that can help, but there's still a lot to think of and each deployment is different.
So why would you wish to bother, given all these complications? This session will discuss precisely that, as well as the tools and pitfalls.

Since each master has to execute the writes from the other anyway, so we're not doing it for write scaling. Sharding is a more effective way to handle that. Instead, multi-master MySQL can be used to ease failover, as well as enable maintenance tasks. It can deliver a system that, even with major upgrades or structural changes, does not require any down time. We all hate that "this website is undergoing maintenance", and it's bad for business. So let's avoid it.