At the time of writing this book, GZRS is in preview. Together with maximum durability, it provides high availability. Data is replicated synchronously across three Azure availability zones. Then, the data is replicated asynchronously to the secondary region. Read access to the secondary region can be enabled as well. GZRS is specially designed to provide at least 99.99999999999999% (16 9s) durability of objects over a given year.