Effect of Switchovers, Failovers, and Control File Creation on Backups

对dataguard 官方文档里面的这句话不理解，是否能给出一个样例说明：
10.2.0.5的版本号
Effect of Switchovers, Failovers, and Control File Creation on Backups

All the archived redo log files that were generated after the last backup on the system
where backups are done must be manually cataloged using the RMAN CATALOG
ARCHIVELOG 'archivelog_name_complete_path' command after any of the following
events:
■ The primary or standby control file is re-created.
Effect of Switchovers, Failovers, and Control File Creation on Backups
Using RMAN to Back Up and Restore Files 10-3
■ The primary database role changes to standby after a switchover.
■ The standby database role changes to primary after switchover or failover.
If the new archived redo log files are not cataloged, RMAN will not back them up.

做了实验，针对standby controlfile 重建情况。

在standby controlfile重建之后，发现standby上的v$archive_log的记录是空的，所以rman 备份的时候会说没有日志。

事实上关键就在这个里，发生上述情况的时候，查看v$archived_log里记录就一目了然了。

另外在重建standby controlfile之后，在这之后archived的日志才会被controlfile记录。备份的时候才会备份到