RMAN-04006: error from auxiliary database

在搭建DG的过程中，之前都是使用备份集恢复数据库的。此次是使用在线恢复，使用duplicate恢复全库，发现报错如下

[oracle@stephenDG admin]$ rman target sys/oracle@stephen auxiliary sys/oracle@stephenDG

Recovery Manager: Release 11.2.0.1.0 - Production on Wed Apr 8 19:36:21 2020

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

connected to target database: STEPHEN (DBID=2427627752)
connected to auxiliary database (not started)

RMAN> duplicate target database for standby nofilenamecheck from active database;

Starting Duplicate Db at 2020-04-08 19:36:50
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of Duplicate Db command at 04/08/2020 19:36:50
RMAN-06403: could not obtain a fully authorized session
RMAN-04006: error from auxiliary database: ORA-01034: ORACLE not available
ORA-27101: shared memory realm does not exist
Linux-x86_64 Error: 2: No such file or directory

此时按照步骤备库是已经启动于 nomount的。
重点在于上面的connected to auxiliary database (not started) 说明数据库没有连接成功。

此错误的原因，是由于备库，没有配置好。我的备库配置有以下错误：
此处的SID_NAME 配置错误，我主备库的sid_name均为stephen，改正后lsnrctl stop&lsnrctl start

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = stephenDG)(PORT = 1521))
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
    )
  )
SID_LIST_LISTENER=
 (SID_LIST =
  (SID_DESC =
        (SID_NAME = PLSExtProc)
        (ORACLE_HOME = /u01/app/oracle/product/11.2.4/db_1)
        (PROGRAM = extproc)
   )
  (SID_DESC =
   (GLOBAL_DBNAME = stephenDG)
   (ORACLE_HOME =/u01/app/oracle/product/11.2.4/db_1)
   (SID_NAME = stephenDG)  
  )
 )

再使用rman登录上去以后，就不会出现not start，而是notmount，此时就可以使用在线恢复命令了

[oracle@stephenDG dbs]$ rman target sys/oracle@stephen auxiliary sys/oracle@stephenDG

Recovery Manager: Release 11.2.0.1.0 - Production on Wed Apr 8 20:26:44 2020

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

connected to target database: STEPHEN (DBID=2427627752)
connected to auxiliary database: STEPHEN (not mounted)