BOL中的建议相当含糊：
Back up master as often as necessary to protect the data sufficiently
for your business needs. We recommend a regular backup schedule,which
you can supplement with an additional backup after a substantial
update.
如果你冒险further,你会发现这些细节：
The types of operations that cause master to be updated,and that
require a backup to take place,include the following:
- Creating or deleting a user database.
- If a user database grows automatically to accommodate new data,
master is not affected.- Adding or removing files and filegroups.
- Adding logins or other operations that are related to login
security.- Database security operations,such as adding a user to a database,
do not affect master.- Changing server-wide or database configuration options.
- Creating or removing logical backup devices.
- Configuring the server for distributed queries and remote procedure
calls (RPCs),such as adding linked servers or remote logins.
因此,如果我们所有的登录都是通过Windows组添加的,并且我们不对数据库进行任何其他更改,这是否意味着对主服务器的一次性备份就足够了？
如果不是,master数据库的标准备份间隔是多少？
