Fleet
Run several servers together: shared DNS, load balancing, moves, failover and shared backups.
A fleet is a group of servers that work together. The Fleet page lists the servers in it and which one is the control node.
DNS cluster answers for the same zones from several servers. Load balancing spreads a site across several web servers, and Moves and failover moves an account to another server or keeps a standby copy ready.
Fleet backups is backup storage the whole fleet shares, run from the control node.