The recovery procedure for system databases depends on the database involved and the problems that you have on your system. In general, recovery may include:
Using load database to load backups of these databases,
Using dataserver, installmaster, and installmodel to restore the initial state of these databases, or
A combination of the above tasks.
To make the recovery of system databases as efficient as possible:
Do not store user databases or any databases other than master, tempdb, model, and sybsystemdb on the master device.
Always keep up-to-date printouts of important system tables.
Always back up the master database after performing actions such as initializing database devices, creating or altering databases, or adding new server logins.
