中心某应用系统使用Netbackup备份软件进行备份。监控邮件告警Nbu备份失败，登录NBU Master服务器进行查看。之前也写过一篇关于status 6的报错解决方法，大家可以看看。http://yangjunfeng.blog.51cto.com/539796/989435
Done status 6：the backup failed to back up the requested files;
赛门铁克官方建议出现 status 6可以到备份脚本所在路径下，找到.out的日志文件进行检查。
root@emdb2 # cat emdb2hot_database_backup.sh.out
Script /opt/oracle/ora_nbu_backup/emdb2hot_database_backup.sh
==== started on Thu Jan 10 14:50:05 CST 2013 ====
RMAN: /opt/oracle/app/oracle/product/11.2.0.3/dbhome_1/bin/rman
ORACLE_SID: emdb2
ORACLE_USER: oracle
ORACLE_HOME: /opt/oracle/app/oracle/product/11.2.0.3/dbhome_1
NB_ORA_FULL: 1
NB_ORA_INCR: 0
NB_ORA_CINC: 0
NB_ORA_SERV: bj-upay-xhm-4f03-p1-m910-nbumas-01
NB_ORA_POLICY: emdb2_ora
Full backup requested
Oracle Corporation SunOS 5.10 Generic Patch January 2005
You have mail.
RMAN> 2> 3> 4> 5> 6> 7> 8> 9> 10> 11> 12> 13> 14> 15> 16> 17> 18> 19> 20> 21> 22> 23> 24> 25> 26> 27> 28> 29> 30> 31> 32> 33> 34> 35> 36> 37> 38> 39> 40> 41> RMAN> cted to target database: EMDB (DBID=1889995907)
using target database control file instead of recovery catalog
RMAN> 2> 3> 4> 5> 6> 7> 8> 9> 10> 11> 12> 13> 14> 15> 16> 17> 18> 19> 20> 21> 22> 23> 24> 25> 26> 27> 28> 29> 30> 31> 32> 33> 34> 35> 36> 37> 38> 39> 40> 41>
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03009: failure of allocate command on ch00 channel at 01/10/2013 14:50:07
ORA-19554: error allocating device, device type: SBT_TAPE, device name:
ORA-27211: Failed to load Media Management Library
Additional information: 2
RMAN>
后询问此数据库管理员其升级过数据库PSU，那么应该就是Netbackup与Oracle直接的link出现问题导致。
nbu在备份是需要调用oracle lib库文件，symantec bin目录下提供了一个脚本来创建link（在数据库服务器上执行）。
oracle@emdb2 # pwd
/usr/openv/netbackup/bin
oracle@emdb2 ./oracle_link
All Oracle instances should be shutdown before running this script.
Please log into the Unix system as the Oracle owner for running this script
Do you want to continue? (y/n) [n] y
LIBOBK path: /usr/openv/netbackup/bin
ORACLE_HOME: /opt/oracle/app/oracle/product/11.2.0.3/db_1
Oracle version: 11.2.0.3.0
Platform type: x86_64
Linking LIBOBK:
ln -s /usr/openv/netbackup/bin/libobk.so64 /opt/oracle/app/oracle/product/11.2.0.3/db_1/lib/libobk.so
Done
这样就会在$ORACLE_HOME/lib/下面生成libobk.os文件，重新发起任务备份成功。
本文转自yangjunfeng 51CTO博客，原文链接:http://blog.51cto.com/yangjunfeng/1114296
