Question: I am attempting to enter
SQL*Plus and I am getting this error:
oracle> sqlplus system/manager@mysid
ORA-12514: TNS: Listener does not currently
know of service requested in connect descriptor
How do I prevent this form of the ORA-12514 error? Also, I often get a TNS-12514 along with the ORA-12514. Are
these the same error? If not, how do I avoid the TNS-12514?
Answer: First, the ORA error is a
permutation of the
ORA-12514: TNS listener cannot resolve service name error as shown
This form of the ORA-12541 error commonly happens when the database
or the listener processes are in the middle of a startup, or when
the database (mysid in your case) has not been registered with the
root> oerr ora 12514
does not currently know of service requested in connect descriptor
The listener received
a request to establish a connection to a database or other service.
The connect descriptor received by the listener specified a service
name for a service (usually a database service) that either has not
yet dynamically registered with the listener or has not been
statically configured for the listener.
This may be a temporary
condition such as after the listener has started, but before the
database instance has registered with the listener.
Wait a moment and
try to connect a second time.
Check which services
are currently known by the listener by executing: lsnrctl services
Check that the
SERVICE_NAME parameter in the connect descriptor of the net
service name used specifies a service known by the listener.
If an easy connect
naming connect identifier was used, check that the service name
specified is a service known by the listener.
Check for an event
in the listener.log file.
To register the database with the listener
You have two options to register your database with the
add a service name to your tnsnames.ora file.
- If you have the multiple listeners and have specified the
database name in your pfile/spfile with local_listener=mysid
then you can dynamically register the database with the
The TNS-12514 is very similar to the ORA-12514 for a reason.
Sometimes Oracle does not get far enough along in the process for an
Oracle error, so a similar network error will appear.
Resolving one should take care of the other.
Read on for specific information on dealing with the
ORA-12514: TNS listener cannot resolve service name error
Question: I have an issue causing a
ORA-12514: TNS: listener could not resolve SERVICE_NAME error:
SQL> shutdown immediate
ORACLE instance shut down.
SQL> startup mount
ORACLE instance started.
TNS:listener could not resolve SERVICE_NAME given in connect
I'm using Oracle 10g on Windows 2000.
What's cause of this error and how to resolve it?
Answer by Edward Stoever:
I avoid using a listener connection when I startup or shutdown, as a
matter of practice. I realize that cannot always be done. Are you
physically on the machine? Can you ssh or telnet in and run sqlplus
on the box? Then connect like so:
export ORACLE_SID=mydb ###Unix/Linux
sqlplus sys as sysdba
[no password needed - just hit return ]
SQL> startup mount
Do not connect with the @mydb to avoid the listener.
Also, Windows systems are subject to a variety of other issues
from screen savers that hog the CPU to the Catch-22 of either
anti-virus protection or a virus interfering with connections.
These conditions and a few others can cause
Also note the similarities in numbering and content for
ORA-12154, which deals with TNS inability to resolve the service
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