two freeradius + 1 db server

Hello again, I'm building a scenario that initially should have: - two redundant freeradius - one mysql server (soon will be a clustered server) Should I be aware of something? I mean if requests goes to both servers, one specific customer auth session will be handled only by that specific freeradius server that received the request? I'm concerned to avoid any kind of inconsistency on my db data. Thanks