Question

The following error messages appear in the listener.log file. What do they mean?


Fatal NI connect error 12537, connecting to:
(DESCRIPTION=(LOCAL=YES)(ADDRESS=(PROTOCOL=beq)))

VERSION INFORMATION:
TNS for Linux: Version 11.1.0.7.0 - Production
Oracle Bequeath NT Protocol Adapter for Linux: Version 11.1.0.7.0 - Prod
uction
Time: 02-MAY-2013 10:48:46
Tracing not turned on.
Tns error struct:
ns main err code: 12537

TNS-12537: TNS:connection closed
ns secondary err code: 12560
nt main err code: 0
nt secondary err code: 0
nt OS err code: 0
Thu May 02 10:55:08 2013

Answer

This is a normal warning message about Oracle listener that can be seen in listener.log, and it indicates that sometimes Oracle Listener is not handling the incoming requests well because:
1) Listener is down and not available;
2) Too many requests at a time that Listener could not handle;
3) Too many database connections and listener cannot handle;
4) Incorrect listener configuration that caused the above warning.

In the case of this customer, the listener.ora in /exlibris/app/oracle/product/11/network/admin was configured with incorrect global_dbname. The value of global_dbname should match exactly the value of the service_names parameter as configured in the database, which normally, is <SID>.<hostname>.
In addition, the tnsnames.ora was updated with full server name instead of short server name.

Category: System Management (500)

Subject: Oracle (500)

• Article last edited: 10/8/2013