Do rsync at the same time to the same destination

I have 10 production servers, What will happen when :

1. I still doi开发者_如何学运维ng rsync for file (A,B,C), meanwhile at the same time my friends also do rsync for file (D,E,F) to the same production machine ?
2. What if i and friends do rsync to the same file at the same time ?

Activity 1 will work just fine. Activity 2 will fail in some unspecified way. If you want to do n-way merges, use a VCS.