How to Synchronize Logins and manage Orphaned Users
Database movement between servers is one of the common task for the DBA. But when the database is moved from one server to another or from one instance to other, the logins do not get transferred. So as a DBA you have to manually transfer the logins to remove this problem.
So let’s discuss what is the cause behind this. SQL Server logins are stored in the master database and they are mapped against individual databases. The Login informations on SQL Server 2005 are visible through sys.server_principals system catalog view and the sys.logins view. The mapping information of the database user is stored in the sysusers system table. This table includes the name of the database user and the SID of the corresponding SQL Server Login. The SID is the security identifier and SID tracks the logins throughout the entire systems.
So when we move or copy our database from one server to another or from one instance to another then the windows login will have the same SID but the SQL logins may have the different SIDs. So when the SID of the new server instance and the older instance doesn’t matches we have a Orphaned User.
