在用rman恢复数据库时，可能会碰到下面的错误，这是由于/backup目录是通过NFS挂载过来的，可通过后面的workaround解决。如果用NFS，建议配置HCA卡，IB交换机，总之带宽要有保障，性能才能好。
ORA-19870: error reading backup piece /backup/db_mqru5153_1_1
ORA-19505: failed to identify file "/backup/db_mqru5153_1_1"ORA-27054: NFS file system where the file is created or resides is not mounted with correct options
Additional information: 6
workaround
在init<ORACLE_SID>.ora修改envent event="10298 trace name context forever, level 32" 或者 sql> alter system set events '10298 trace name context forever, level 32'; sql> alter system set events '10298 trace name context forever, level 32' scope=spfile;
