Legato异机恢复oracle报错，rman没有任何错误日志：
 ORA-19870: error reading backup piece full_open_IEBDPR01_h7k7ccrn_1575
 ORA-19507: failed to retrieve sequential file, handle="xxx", parms=""
 ORA-27029: skgfrtrv: sbtrestore returned error
 ORA-19511: Error received from media manager layer, error text:
 A backup or restore session is already in progress. (100:17:0)
 failover to previous backup

Server端remote access已经添加，测试客户端不通：
 [root@bip-bdb02 ~]# nsrinfo -s xxx -n oracle yyy
 scanning client `yyy' for all savetimes from the oracle namespace on server xxx
 9714:nsrinfo: cannot start session with server xxx
 39078:nsrinfo: File index error: permission denied, `root' on `zzz' must have the 'Operate NetWorker' privilege OR the 'Recover Local Data' privilege for the client 'zzz'

查询资料如下：
 The user must have the privileges:
        Monitor NetWorker
        Backup Local Data
        Recover Local Data
 
 In you case, you must also grant him:
        Configure NetWorker
        Operate NetWorker
 
 As the deletion is a a configuration issue, this will of course also be possible.
 Do not forget to monitor changes to the configuration (NW server - Monitor RAP option).
 
 On the other hand, you could also advise him to run the same group from the
 command line, just for a specific client:
        savegrp [-l level] -C client -G group
 In this case, there is no need for a re-configuration ;-).
 
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在legato server端添加相应的权限，问题解决：
 [oracle@bip-bdb02 ~]$ nsrinfo -s xxx -n oracle yyy
 scanning client `OG2222-DBS301' for all savetimes from the oracle namespace on server xxx
 c-3169346478-20120511-02, date=1336715768 Fri 11 May 2012 01:56:08 PM CST
 cananf78_1_1, date=1336715752 Fri 11 May 2012 01:55:52 PM CST
 c-3169346478-20120511-01, date=1336714214 Fri 11 May 2012 01:30:14 PM CST
 c8nandml_1_1, date=1336714198 Fri 11 May 2012 01:29:58 PM CST
 c-3169346478-20120511-00, date=1336714055 Fri 11 May 2012 01:27:35 PM CST
 c6nandhc_1_1, date=1336714028 Fri 11 May 2012 01:27:08 PM CST
 6 objects found