今天数据库负载量比较大，结果报错了：
ORA-03113: end-of-file on communication channel
找到告警日志位置，并查看：
SQL> sho parameter background_dump_dest;
NAME TYPE
VALUE
------------------------------------ ----------- ------------------------------
background_dump_dest string/u01/diag/rdbms/zydb/zydb/trac
e
[root@localhost trace]# vi /u01/diag/rdbms/zydb/zydb/trace/alert_zydb.log
Errors in file /u01/diag/rdbms/zydb/zydb/trace/zydb_m000_49294.trc:
ORA-19815: WARNING: db_recovery_file_dest_size of 4070572032 bytes is 85.14% used, and has 604814336 remaining bytes available.
************************************************************************
You have following choices to free up space from recovery area:
1. Consider changing RMAN RETENTION POLICY. If you are using Data Guard,
then consider changing RMAN ARCHIVELOG DELETION POLICY.
2. Back up files to tertiary device such as tape using RMAN
BACKUP RECOVERY AREA command.
3. Add disk space and increase db_recovery_file_dest_size parameter to
reflect the new space.
4. Delete unnecessary files using RMAN DELETE command. If an operating
system command was used to delete files, then use RMAN CROSSCHECK and
DELETE EXPIRED commands.
*******************************
处理过程：
备份过期的归档日志，然后删除，
用PL\SQL重新连接报错：ORA-00257：archiver error. Connect internal only,until freed.
使用rman，清理过期的数据:
[oracle@localhost 2014_02_24]$ rman target/
Recovery Manager: Release 11.2.0.1.0 - Production on Mon Feb 24 16:43:57 2014
Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved.
connected to target database: ZYDB (DBID=2363673059)
RMAN> crosscheck archivelog all;
RMAN> delete expired archivelog all;
删除后问题解决
网上还有一种方法：
增大db_recovery_file_dest_size参数的值，
SQL> sho parameter db_recovery_file_dest_size;
NAME TYPE
VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest_size big integer 3882M
SQL> alter system set db_recovery_file_dest_size=5112M;
System altered.
SQL> sho parameter db_recovery_file_dest_size;
NAME TYPE
VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest_size big integer 5112M
ORA-03113: end-of-file on communication channel
原文：http://blog.csdn.net/pengpengfly_jhp/article/details/19830967