记录一则数据库连接故障ORA-12560,ORA-12518

环境：Win Server 2008 R2 + Oracle 11.2.0.1故障：客户反映数据库连接不上，本机sysdba和网络连接都连接不上。

一、确认故障

• 1.1 服务器尝试sysdba登录
• 1.2 服务器尝试通过网络连接

二、排查原因

• 2.1 ORA-12560错误初步排查原因
• 2.2 ORA-12518错误排查原因
• 2.3 ORA-12560错误再次排查原因

一、确认故障

1.1 服务器尝试sysdba登录

PS C:/Users/Administrator> sqlplus / as sysdba  SQL*Plus: Release 11.2.0.1.0 Production on 星期四 2月 18 09:39:14 2016  Copyright (c) 1982, 2010, Oracle.  All rights reserved.  ERROR: ORA-12560: TNS: 协议适配器错误

1.2 服务器尝试通过网络连接

PS C:/Users/Administrator> sqlplus system/oracle@xxoradb  SQL*Plus: Release 11.2.0.1.0 Production on 星期四 2月 18 09:34:01 2016  Copyright (c) 1982, 2010, Oracle.  All rights reserved.  ERROR: ORA-12518: TNS: 监听程序无法分发客户机连接

二、排查原因

2.1 ORA-12560错误初步排查原因

ORA-12560错误官方说明：

$ oerr ora 12560 12560, 00000, "TNS:protocol adapter error" // *Cause: A generic protocol adapter error occurred. // *Action: Check addresses used for proper protocol specification. Before // reporting this error, look at the error stack and check for lower level // transport errors. For further details, turn on tracing and reexecute the // operation. Turn off tracing when the operation is complete.

MOS相关文档：Bequeath connection fails with ORA-12560 on Windows (文档 ID 1986438.1)可能原因：

解决方法：

由于业务目前已经是中断状态，所以可以重启监听和数据库服务，检查注册表信息，但问题依旧。这里实际走了弯路，因为sqlplus命令是正常使用的，所以在环境变量方面就没多想PATH的问题。

2.2 ORA-12518错误排查原因

ORA-12518错误官方说明：

$ oerr ora 12518 12518, 00000, "TNS:listener could not hand off client connection" // *Cause: The process of handing off a client connection to another process // failed. // *Action: Turn on listener tracing and re-execute the operation. Verify // that the listener and database instance are properly configured for // direct handoff.  If problem persists, call Oracle Support. // *Comment: The problem can be worked around by configuring dispatcher(s) // to specifically handle the desired presentation(s), and connecting // directly to the dispatcher, bypassing the listener.

查看当前监听配置文件：

# listener.ora Network Configuration File: D:/app/Administrator/product/11.2.0/dbhome_1/network/admin/listener.ora # Generated by Oracle configuration tools.  SID_LIST_LISTENER =   (SID_LIST =     (SID_DESC =       (SID_NAME = CLRExtProc)       (ORACLE_HOME = D:/app/Administrator/product/11.2.0/dbhome_1)       (PROGRAM = extproc)       (ENVS = "EXTPROC_DLLS=ONLY:D:/app/Administrator/product/11.2.0/dbhome_1/bin/oraclr11.dll")     )   )  LISTENER =   (DESCRIPTION_LIST =     (DESCRIPTION =       (ADDRESS = (PROTOCOL = TCP)(HOST = WIN-1XXXXXXXXXX)(PORT = 1521))       (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC521))     )   )  ADR_BASE_LISTENER = D:/app/Administrator

修改监听配置文件加入静态监听配置内容：

# listener.ora Network Configuration File: D:/app/Administrator/product/11.2.0/dbhome_1/network/admin/listener.ora # Generated by Oracle configuration tools.  SID_LIST_LISTENER =   (SID_LIST =     (SID_DESC =       (SID_NAME = CLRExtProc)       (ORACLE_HOME = D:/app/Administrator/product/11.2.0/dbhome_1)       (PROGRAM = extproc)       (ENVS = "EXTPROC_DLLS=ONLY:D:/app/Administrator/product/11.2.0/dbhome_1/bin/oraclr11.dll")     )     (SID_DESC =       (GLOBAL_DBNAME = xxoradb)       (ORACLE_HOME = D:/app/Administrator/product/11.2.0/dbhome_1)       (SID_NAME = xxoradb)     )   )  LISTENER =   (DESCRIPTION_LIST =     (DESCRIPTION =       (ADDRESS = (PROTOCOL = TCP)(HOST = WIN-1XXXXXXXXXX)(PORT = 1521))       (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC521))     )   )  ADR_BASE_LISTENER = D:/app/Administrator

重启监听后再测试，发现加入静态监听后可以连接到数据库了，同时服务器上的PL/SQL工具也可以正常连接到数据库了。

C:/Users/Administrator>sqlplus system/oracle@xxoradb  SQL*Plus: Release 11.2.0.1.0 Production on 星期四 2月 18 10:52:24 2016  Copyright (c) 1982, 2010, Oracle.  All rights reserved.   连接到: Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options  SQL>

这样，就先解决了客户端网络连接的问题。

2.3 ORA-12560错误再次排查原因

上面解决了客户端的连接问题，但问题还没有完美解决，因为目前本地sysdba仍然还是无法登陆，依然报错ORA-12560：

C:/Users/Administrator>sqlplus / as sysdba  SQL*Plus: Release 11.2.0.1.0 Production on 星期四 2月 18 10:59:11 2016  Copyright (c) 1982, 2010, Oracle.  All rights reserved.  ERROR: ORA-12560: TNS: 协议适配器错误   请输入用户名:

看到Oracle产品目录下，11.2.0文件夹下有多个文件夹存在

D:/app/Administrator/product/11.2.0>dir  驱动器 D 中的卷没有标签。  卷的序列号是 0A43-E08A   D:/app/Administrator/product/11.2.0 的目录  2016/01/26  12:26    <DIR>          . 2016/01/26  12:26    <DIR>          .. 2016/01/26  12:35    <DIR>          client_1 2016/01/26  12:23    <DIR>          dbhome_1 2016/01/26  12:25    <DIR>          dbhome_2                0 个文件              0 字节                5 个目录 200,137,936,896 可用字节

看起来的确安装有多个Oracle软件，从命名规则来看，应该是1个客户端，两个DB。

D:/app/Administrator/product/11.2.0/client_1/BIN;D:/app/Administrator/product/11.2.0/dbhome_1/BIN;D:/app/Administrator/product/11.2.0/dbhome_1;C:/Program Files (x86)/Common Files/NetSarang;%SystemRoot%/system32;%SystemRoot%;%SystemRoot%/System32/Wbem;%SYSTEMROOT%/System32/WindowsPowerShell/v1.0/

C:/Users/Administrator>sqlplus / as sysdba  SQL*Plus: Release 11.2.0.1.0 Production on 星期四 2月 18 11:16:53 2016  Copyright (c) 1982, 2010, Oracle.  All rights reserved.   连接到: Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options  SQL>

最后，再确认下，PL/SQL等工具也可以重新正常登录。至此，问题完美解决。