Cannot connect to ExtProc in Oracle 11g

Question

We have two instances of Oracle on the same server (both 11g) that use the same listener. I had a problem connecting to extproc:

TNSNAMES.ORA

EXTPROC_CONNECTION_DATA.NATIONAL.SERVER.COM = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC11G)) ) (CONNECT_DATA = (SERVICE_NAME = PLSExtProc11g) ) ) 

LISTENER.ORA

 (DESCRIPTION_LIST= (DESCRIPTION = (ADDRESS_LIST= (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521)) (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC11G)) ) ) ) SID_LIST_LISTENER = (SID_LIST = (SID_DESC = (SID_NAME = PLSExtProc11g) (ORACLE_HOME = /home/app/oracle/product/11.2.0/dbhome_1) (ENVS = "EXTPROC_DLLS=ANY") (PROGRAM = extproc) ) 

When I use TNSPING to test the connection, I get the following:

/home/app/oracle/product/11.2.0/dbhome_1/network/admin/sqlnet.ora

$ tnsping EXTPROC_CONNECTION_DATA

TNS Ping Utility for Linux: Version 11.2.0.1.0 - Production 03-NOV-2011 14:03:41

Copyright (c) 1997, 2009, Oracle. All rights reserved.

Parameter files used:

The TNSNAMES adapter is used to resolve the alias Attempt to contact (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = IPC) (KEY = EXTPROC11G))) (CONNECT_DATA = (SERVICE_NAME = PLSExtProc11g))) TNS-12541: TNS: no listener

I can successfully use both databases, but not EXTPROC_CONNECTION_DATA.

Answer 1

In this particular case, the listener.ora file had an explicitly hidden type. Using netca to reconfigure the listener resolved the issue.

Answer 2

change SID_NAME to the correct value, this may fix the problem.

example: (SID_NAME = PLSExtProc11g) in (SID_NAME = ORCL)