Ora-12541:TNS:no listener

[ick1383]

Hello all,

I run an application based on Oracle 8.1.7 (Server OS: Windows 2000 SP4) and all of a sudden, on a random basis, I started to get an error message on client machines - "Ora-12541:TNS:no listener", not being able then to connect to the db. The problem happens more often on a client machine where I have the Web Server of my application.

The OracleOra817TNSListener service is started and I even if I stop and restart it, or try the "lsnrctl stop/start" commands, the error persists. After rebooting the server the application runs fine, but after a while the message starts to come up again on a the client side.

The TNSNAMES.ORA on the client matches the file with the same name on the server. The TNSPING on the client side runs fine and then suddenly I get the NO LISTENER error.

I performed a fresh installation in the beginning of the year and just recently I started to get this error. I also read some previous messages on this forum regarding the error but could not conclude what is happening at my environment.

I would appreciate any help. Thank you very much!
Ivo

[marist89]

Can you verify that the listener is going up and down?

[ick1383]

I am not sure if I understand your question, but even when I get the error, the service is up and running. Also, even typing lsnrctl stop/start the error persists.

Thank you!!

[marist89]

Put it another way, is your listener really going up and down or is it always up even when you get these error messages?

[ick1383]

It is always up even when I get these error messages. Again, everything is running fine and all of a sudden the error message appears. Then, after rebooting the client machine I can connect correctly to the db on the server until I get the error again (on the client side).

Thank you again!

[marist89]

I'd be looking at two things:
1. make sure the instance is registered in the listener.ora.
2. make sure your local_listener parameter in the init.ora is pointing to the correct listener.

[ick1383]

On the server machine I do have a init.ora, but it does not have a local_listener parameter. There is no such file on the client side.

The listener.ora on the server machine is like this:

# LISTENER.ORA Network Configuration File: C:\oracle\ora817\network\admin\listener.ora
# Generated by Oracle configuration tools.

LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC0))
)
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = dx06smt3)(PORT = 1521))
)
)
(DESCRIPTION =
(PROTOCOL_STACK =
(PRESENTATION = GIOP)
(SESSION = RAW)
)
(ADDRESS = (PROTOCOL = TCP)(HOST = dx06smt3)(PORT = 2481))
)
)

SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = C:\oracle\ora817)
(PROGRAM = extproc)
)
(SID_DESC =
(GLOBAL_DBNAME = decasp.dx06)
(ORACLE_HOME = C:\oracle\ora817)
(SID_NAME = decasp)
)
)

The Global name, SID, Oracle home and Host entries are all correct.

What really surprises me is that, as I mentioned before, the problem happens more often on a client machine where I have the Web Server of my application and not on the other Win32 client machines.

Thank you!!

[Mohd Jun]

Put it another way, is your listener really going up and down or is it always up even when you get these error messages?

Hi, there. I have the same problem. Please read below error details; Please assist.

"Fatal NI connect error 12541, connecting to:
(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=MohdJun)(PORT=1521))(CONNECT_DATA=(SERVER=DEDICATED)(SERVI CE_NAME=XE)(CID=(PROGRAM=C:\Primavera\Project Management\pm.exe)(HOST=MOHDJUN)(USER=user))))

VERSION INFORMATION:
TNS for 32-bit Windows: Version 10.2.0.1.0 - Production
Windows NT TCP/IP NT Protocol Adapter for 32-bit Windows: Version 10.2.0.1.0 - Production
Time: 10-JUL-2017 08:49:59
Tracing not turned on.
Tns error struct:
ns main err code: 12541
TNS-12541: TNS:no listener
ns secondary err code: 12560
nt main err code: 511
TNS-00511: No listener
nt secondary err code: 61
nt OS err code: 0"

[Mohd Jun]

Hi Jeff,

I have also similar error on my database. Below is the details. Thanks for your help.

Fatal NI connect error 12541, connecting to:
(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=MohdJun)(PORT=1521))(CONNECT_DATA=(SERVER=DEDICATED)(SERVI CE_NAME=XE)(CID=(PROGRAM=C:\Primavera\Project Management\pm.exe)(HOST=MOHDJUN)(USER=user))))

VERSION INFORMATION:
TNS for 32-bit Windows: Version 10.2.0.1.0 - Production
Windows NT TCP/IP NT Protocol Adapter for 32-bit Windows: Version 10.2.0.1.0 - Production
Time: 10-JUL-2017 08:49:59
Tracing not turned on.
Tns error struct:
ns main err code: 12541
TNS-12541: TNS:no listener
ns secondary err code: 12560
nt main err code: 511
TNS-00511: No listener
nt secondary err code: 61
nt OS err code: 0

[gandolf989]

You should not add comments to 11 year old posts in order to get help.
I answered your other post. I am closing this post to prevent further comments.