What is the least amount of privileges (Administrator, db_owner, etc ) for a user to perform Backup and Restore in SQL Server?

Question

What is the least amount of privileges (Administrator, db_owner, etc) for a user to perform following in SQL Server ?

1. Backup
2. Restore

Answer 1

For backups the db_backupoperator fixed database role is the least amount of privileges needed.

https://msdn.microsoft.com/en-gb/library/ms187510.aspx

For Restores, If the database being restored does not exist, the user must have CREATE DATABASE permissions to be able to execute RESTORE.

https://msdn.microsoft.com/en-gb/library/ms186858.aspx

Answer 2

As stated in the documentation...

Restore

If the database being restored does not exist, the user must have CREATE DATABASE permissions to be able to execute RESTORE. If the database exists, RESTORE permissions default to members of the sysadmin and dbcreator fixed server roles and the owner (dbo) of the database (for the FROM DATABASE_SNAPSHOT option, the database always exists).

RESTORE permissions are given to roles in which membership information is always readily available to the server. Because fixed database role membership can be checked only when the database is accessible and undamaged, which is not always the case when RESTORE is executed, members of the db_owner fixed database role do not have RESTORE permissions.

Backup

BACKUP DATABASE and BACKUP LOG permissions default to members of the sysadmin fixed server role and the db_owner and db_backupoperator fixed database roles.