Symptoms: 

For your master database you might find different configuration such as Backup Storage Redundancy configured to be Local or Geo

As this is not configurable property you might ask why is my database configured with this value. 

Resolution: 

For master database on Azure SQL Database Server, Microsoft is managing this database as part of the server entity. 

as you cannot change the SLO level (which might be system or system2) for the master database there are other properties that cannot be configured from customer end. 

Note that master database is part of the server entity and should not store user data, therefore the only use of master database is to operate the server object. 

Backup redundancy is displayed as this is one of the properties shown for database object, however this is irrelevant for master database.

in any case, Microsoft implement mechanisms to keep this database highly available and secure for your database server. 

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