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Azure SQL Managed Instance and the master Database
The master database records all the system-level information, including metadata, which is logon accounts, endpoints, linked servers, and system configuration settings. It is a best practice to keep your master database static.
When you use Azure SQL Managed Instance, you cannot update a master database, and it is not recommended to create objects in the master database. For example, if your master database is rebuilt, all objects will be lost.
See Also
Roles and Permissions for Datical DB and Azure SQL Managed Instance
Creating Connections in Datical DB and Azure SQL Managed Instance
Packager backup and restore process for SQL Server and Azure SQL Managed Instance
The ephemeralConnectionRetryTimeout property for Azure SQL Managed Instance
Troubleshooting Issues with Active Directory Authentication and Azure Managed Instance
Automated backups - Azure SQL Database & SQL Managed Instance