SQL Azure Failover [FAQ]

One of the key benefits of Azure is the inbuilt failover protection, in the event of a hardware failure the automatic failover kicks in and a mirror of the database is brought online. This failover is not completely seemless as the current sessions will first be disconnected and then must be reconnected. If the fail occurs during a transaction, that transaction is then rolled back.

In addition there is inbuilt DOS protection, if there are many failed attempts to access a SQL Azure database the requesting IP is disallowed for a period of time. Thus if you make several incorrect login attempts you may be locked out for a short period.