现象：client进行sqlplus连接时，报此错误，并提示tnsname无法连接。
解决方案：更改listener.ora文件
原来的文件：
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = /u01/app/oracle/product/10.1.0/db_1)
(PROGRAM = extproc)
)
)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = dtberp)(PORT = 1521))
)
)
)
更改后：
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = /u01/app/oracle/product/10.1.0/db_1)
(PROGRAM = extproc)
)
(SID_DESC =
(SID_NAME = dtberp)
(ORACLE_HOME = /u01/app/oracle/product/10.1.0/db_1)
(GLOBAL_DBNAME = dtberp)
)
)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = dtberp)(PORT = 1521))
)
)
)
