Amazon Aurora

Amazon Aurora allows creating up 15 read replicas in a region. Read replicas share the source storage.

Storage scales automatically into 10GB increments up to 64 TB.

There is option for Global Database which allows single database to span across multiple regions.  It uses storage based replication.

By default Aurora database is replicated six ways across three AZs. It can handle loss of two copies without affecting writes and three copies without affecting reads.

Aurora also has a backtrack feature, it can go back to point in time without restore from a backup. 

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