oracle10 用户无法连接到指定实例

问题1：tns：could‘not find the identified
   
   查看$ORACLE_HOME/network/admin/ 下的listern.ora  还有tnsnames.ora 两个文件
   如下配置
  
   # listener.ora Network Configuration File: /home/oracle/db/oracle/product/11.1.0/db_1/network/admin/listener.ora（红色字体为增加内容）
# Generated by Oracle configuration tools.

SID_LIST_LISTENER =
   (SID_LIST =
    (SID_DESC =
      (GLOBAL_DBNAME = ORCL)
      (ORACLE_HOME =/home/oracle/db/oracle/product/11.1.0/db_1)
      (SID_NAME = ORCL)
    )
    (SID_DESC =
      (SID_NAME = ovtpm)
      (ORACLE_HOME =/home/oracle/db/oracle/product/11.1.0/db_1)
     # (PROGRAM = extproc)
     # (ENVS = "EXTPROC_DLLS=ONLY:/home/oracle/db/oracle/product/11.1.0/db_1/bin/oraclr11.dll")
    )
  )


LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
      (ADDRESS = (PROTOCOL = TCP)(HOST = ldzhang)(PORT = 1521))
    )
  )



---tnsnames.ora
  # tnsnames.ora Network Configuration File: /home/oracle/db/oracle/product/11.1.0/db_1/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.

LISTENER_ORCL = 
  (ADDRESS = (PROTOCOL = TCP)(HOST = ldzhang)(PORT = 1521)) 
 

OVTPM = 
  (DESCRIPTION = 
    (ADDRESS_LIST = 
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521)) 
    ) 
    (CONNECT_DATA = 
      (SID = ovtpm) 
      (PRESENTATION = RO) 
    ) 
  ) 




ORCL =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = ldzhang)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl.localdomain)
    )
  )


记得将host 的value 改为主机名（linux  用hostname可查看） 或是  主机的ip


问题2：ORA-28547: connection to server failed, probable Oracle Net admin error

将listener.ora 中的   (PROGRAM = extproc) 注释

且配置sqlnet.ora如下
  # sqlnet.ora Network Configuration File: /home/oracle/db/oracle/product/11.1.0/db_1/network/admin/sqlnet.ora
# Generated by Oracle configuration tools.
#SQLNET.AUTHENTICATION_SERVICES = (NTS)
SQLNET.AUTHENTICATION_SERVICES = (BEQ,NONE)
NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)