开启归档模式
> archive log list;
> shutdown immediate;
> startup mount
> alter database archivelog
> alter database open;
> archive log list;
查看归档模式，同时还能看归档存放路径
> show parameter recovery;
查看当前的重做日志组
> select group#,status,bytes,archived from v$log;
手工切换重做日志组，将其归档
> alter system switch logfile;
这个时候再看就已经显示切换了
> select group#,status,bytes,archived from v$log;
修改归档日志的路径
> alter system set log_archive_dest_1='location=/data/archivelog' scope=spfile;
修改归档目录大小
> alter system set DB_RECOVERY_FILE_DEST_SIZE=20g;
关闭归档
> alter database noarchivelog