在Oracle 11g，开启archive log模式时，默认归档目录为db_recovery_file_dest指定。此参数在pfile/spfile中可以指定：
show parameter db_recovery_file_dest
db_recovery_file_dest=/oracle/11g/flash_recovery_area
更改归档模式
需要在mount状态下，更改归档模式。
SQL> shutdown immediate;
SQL> startup mount
SQL> alterdatabase archivelog; / alter database noarchivelog
Database altered.
SQL> alter database open;
SQL> archive log list;
[email protected]> archive log list;
Database log mode Archive Mode
Automatic archival Enabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 53
Next log sequence to archive 55
Current log sequence 55
更改log_archive_dest_1参数可更改归档日志目录（pfile/spfile中参数db_recovery_file_dest指定的目录将无效）
SQL> alter system setlog_archive_dest_1=‘location=/data/oracle/log1/archive_log‘; 最后的目录名称需要为archive_log!
System altered.
SQL> archive log list;
Database log mode Archive Mode
Automatic archival Enabled
Archive destination /data/oracle/log1/archive_log
Oldest online log sequence 26
Next log sequence to archive 28
Current log sequence 28
SQL> alter system archive log current;
System altered.
[email protected]> select name fromv$archived_log;
NAME
-----------------------------------
/oracle/11g/flash_recovery_area/ORC
L/archivelog/2015_12_11/o1_mf_1_55_
c6nyryhs_.arc
修改日志文件命名格式：
SQL> alter system setlog_archive_max_processes = 5;
SQL> alter system set log_archive_format= "archive_%t_%s_%r.log" scope=spfile;
*****************************************************************************************************************
SQL>archive log list;
如果显示为ENABLE则表示已成功归档
或 SQL>select log_mode fromv$database;
如果为ARCHIVELOG则表示已成功归档
********************************************************************************
SQL> show parameter db_recovery
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest string /data/oracle/flash_recovery_area
db_recovery_file_dest_size biginteger 4231m
可以修改db_recovery_file_dest_size参数的大小
SQL>alter system setdb_recovery_file_dest_size=21474836480