Oracle 11g 的新特性Duplicate Active Database可以在不备份target database的情况下构建 duplicate database，特别适合于为VLDB构建standby的场景。今天特意试一下，但是却让我遇上了 ORA-01017 invalid username/password，过程如下：

oracle@dev18:abank /home/oracle>rman target / auxiliary sys/__password__@abank_123 

Recovery Manager: Release 11.2.0.1.0 - Production on Sun May 29 14:16:08 2011

Copyright (c) 1982, 2009, Oracle and/or its affiliates.  All rights reserved.

connected to target database: abank (DBID=433589790)
connected to auxiliary database: abank (not mounted)

RMAN> duplicate target database for standby from active database ;  

Starting Duplicate Db at 2011-05-29 14:16:17
using target database control file instead of recovery catalog
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=1149 device type=DISK

contents of Memory Script:
{
   backup as copy reuse
   targetfile  '/opt/app/oracle/product/11.2.0/db/dbs/orapwabank' auxiliary format 
 '/opt/app/oracle/product/11.2.0/db/dbs/orapwabank'   ;
}
executing Memory Script

Starting backup at 2011-05-29 14:16:18
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=594 device type=DISK
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of Duplicate Db command at 05/29/2011 14:16:19
RMAN-03015: error occurred in stored script Memory Script
RMAN-03009: failure of backup command on ORA_DISK_1 channel at 05/29/2011 14:16:19
ORA-17629: Cannot connect to the remote database server
ORA-17627: ORA-01017: invalid username/password; logon denied
ORA-17629: Cannot connect to the remote database server

      打开rman的时候已经进行了验证，理论上不应在有验证的问题，google得知使用Duplicate Active Database要这样登入rman：

rman target sys/__password__ auxiliary sys/__password__@abank_123