In the event of a schema change we will be taking down the master node and one slave node, rebuilding replication on them then doing the other slave nodes one at a time.

Ex we have 3 slave nodes.
This is how I envision it going.
- Update schema on master & slave 1
- Create replication set on master & slave 1
- Update schema on slave 2
- Add slave 2 to replication set
- Update schema on slave 3
- Add slave 3 to replication set