Dump the master Database After Each Change

Although you can restrict the creation of database objects in master, commands such as create login and drop login, and alter login allow users to modify system tables in the database. Back up the master database frequently to record these changes.

Back up the master database after each command that affects disks, storage, databases, or segments. Always back up master after issuing any of the following commands or system procedures:

disk init, sp_addumpdevice, or sp_dropdevice
Disk mirroring commands
The segment system procedures sp_addsegment, sp_dropsegment, or sp_extendsegment
create procedure or drop procedure
sp_logdevice
sp_configure
create database or alter database