Ora-12541:TNS:no listener

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

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

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!!

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

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!

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.

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!!

Quote:

---

Originally Posted by 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?

---

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"

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

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.