|
 |
|
Oracle listener ORA-12500 Tips
Don Burleson
|
The "ORA-12500: TNS: listener failed to start a dedicated server process"
appears when Oracle does not have enough PGA RAM to spawn a process
for a new Oracle connection.
ORA-12500: TNS:listener failed to
start a dedicated server process
Cause: The process of starting up a
dedicated server process failed. The executable could not be
found or the environment may be set up incorrectly.
Action: Turn on tracing at the ADMIN
level and reexecute the operation. Verify that the ORACLE Server
executable is present and has execute permissions enabled.
Ensure that the ORACLE environment is specified correctly in
LISTENER.ORA. The Oracle Protocol Adapter that is being called
may not be installed on the local hard drive. Please check that
the correct Protocol Adapter are successfully linked. If error
persists, contact Oracle Customer Support.
The most common cause of a ORA-12500 is a busy
system whereby PGA RAM is exhausted. The solutions are:
-
Reduce sort_area_size
(pga_aggregate_target) and hash_area_size to make each default
PGA size smaller.
-
Add additional server RAM
-
As a last resort, deploy shared servers
(the Multithreaded Server (MTS).
Common syntax issues in the listener.ora file can
cause numerous listener connection problems, most notably the "ORA-12500: TNS: listener failed to start a dedicated server process"
error.
Sometimes this ORA-12500 is because of a PGA
RAM shortage on the target database, based on the settings for
pga_aggregate_target, sort_area_size and hash_area_size.
You can have a single listener, pointing to
multiple Oracle instances, each on a different version.
In Windows, especially Oracle8 and
Oracle8i, you may need to re-start the listener service using the
Windows task manager.
|
