I am new on Oracle database, but I have one issue.
On my Database server (server1) listener and database instance run correctly and I can use sqlplus
to connect to this DB.
When I connect to database by using other server, I check the TNS configuration and it is correct but system says:
ERROR: ORA-12541: TNS:no listener
My database is Oracle 10gR2
So how can I solve this issue?
Gryu
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asked Nov 13, 2012 at 9:58
10
You need to set oracle to listen on all ip addresses (by default, it listens only to localhost connections.)
Step 1 — Edit listener.ora
This file is located in:
- Windows:
%ORACLE_HOME%\network\admin\listener.ora
. - Linux: $ORACLE_HOME/network/admin/listener.ora
Replace localhost
with 0.0.0.0
# ...
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = 0.0.0.0)(PORT = 1521))
)
)
# ...
Step 2 — Restart Oracle services
-
Windows: WinKey + r
services.msc
-
Linux (CentOs):
sudo systemctl restart oracle-xe
answered Feb 19, 2014 at 14:58
Mikael HolmgrenMikael Holmgren
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10
I also faced the same problem but I resolved the issue by starting the TNS listener in control panel -> administrative tools -> services ->oracle TNS listener start.I am using windows Xp and Toad to connect to Oracle.
answered Jul 1, 2013 at 5:53
subhashissubhashis
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2
Check out your TNS Names, this must not have spaces at the left side of the ALIAS
Best regards
answered Oct 31, 2013 at 0:31
ArmandArmand
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0
According to oracle online documentation
ORA-12541: TNS:no listener
Cause: The connection request could not be completed because the listener is not running.
Action: Ensure that the supplied destination address matches one of the addresses used by
the listener - compare the TNSNAMES.ORA entry with the appropriate LISTENER.ORA file (or
TNSNAV.ORA if the connection is to go by way of an Interchange). Start the listener on
the remote machine.
answered Nov 13, 2012 at 11:37
dariyooshdariyoosh
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1
I am new on Oracle database, but I have one issue.
On my Database server (server1) listener and database instance run correctly and I can use sqlplus
to connect to this DB.
When I connect to database by using other server, I check the TNS configuration and it is correct but system says:
ERROR: ORA-12541: TNS:no listener
My database is Oracle 10gR2
So how can I solve this issue?
Gryu
2,1122 gold badges17 silver badges29 bronze badges
asked Nov 13, 2012 at 9:58
10
You need to set oracle to listen on all ip addresses (by default, it listens only to localhost connections.)
Step 1 — Edit listener.ora
This file is located in:
- Windows:
%ORACLE_HOME%\network\admin\listener.ora
. - Linux: $ORACLE_HOME/network/admin/listener.ora
Replace localhost
with 0.0.0.0
# ...
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = 0.0.0.0)(PORT = 1521))
)
)
# ...
Step 2 — Restart Oracle services
-
Windows: WinKey + r
services.msc
-
Linux (CentOs):
sudo systemctl restart oracle-xe
answered Feb 19, 2014 at 14:58
Mikael HolmgrenMikael Holmgren
2,4661 gold badge18 silver badges27 bronze badges
10
I also faced the same problem but I resolved the issue by starting the TNS listener in control panel -> administrative tools -> services ->oracle TNS listener start.I am using windows Xp and Toad to connect to Oracle.
answered Jul 1, 2013 at 5:53
subhashissubhashis
4,6298 gold badges37 silver badges52 bronze badges
2
Check out your TNS Names, this must not have spaces at the left side of the ALIAS
Best regards
answered Oct 31, 2013 at 0:31
ArmandArmand
611 silver badge5 bronze badges
0
According to oracle online documentation
ORA-12541: TNS:no listener
Cause: The connection request could not be completed because the listener is not running.
Action: Ensure that the supplied destination address matches one of the addresses used by
the listener - compare the TNSNAMES.ORA entry with the appropriate LISTENER.ORA file (or
TNSNAV.ORA if the connection is to go by way of an Interchange). Start the listener on
the remote machine.
answered Nov 13, 2012 at 11:37
dariyooshdariyoosh
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1
ORA-12541 is the same as TNS-12541, they all indicate that the listener is not running according to your specified destination.
Let’s see how we reproduce ORA-12541 and TNS-12541.
SQL*Plus throws ORA-12541
SQL> conn hr/hr@orcl
ERROR:
ORA-12541: TNS:no listener
TNSPING throws TNS-12541
C:\Users\ed>tnsping compdb
TNS Ping Utility for 64-bit Windows: Version 12.1.0.1.0 - Production on 22-JUL-2014 19:20:06
Copyright (c) 1997, 2013, Oracle. All rights reserved.
Used parameter files:
C:\oracle\app\client\ed\product\12.1.0\client_1\network\admin\sqlnet.ora
Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = primary01)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = compdb)))
TNS-12541: TNS:no listener
Cause
The connection cannot find the listener, it could be:
- The listener is not started.
- The listener is listening to another port other than the default one, e.g. 1522.
- The connection went for the wrong database server.
- Routing to the wrong destination.
This is the most common problem of ORA-12541 we have met. Just start it up and make sure it’s running.
Backup port like 1522 may be used by the listener for connection, you should ask for DBA to handle it.
Please check every parameter in your connect descriptor and make sure they are correct. Then connect again.
It’s rare, but it did happen in a very complex network environment. Part of connections are routed by some network device to an unknown server where has no listener service on port 1521.
Solution
Check the status and port of LISTENER on server side and start it if necessary.
[oracle@primary01 ~]$ lsnrctl status
LSNRCTL for Linux: Version 12.1.0.1.0 - Production on 22-JUL-2014 19:22:34
Copyright (c) 1991, 2013, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
TNS-12541: TNS:no listener
TNS-12560: TNS:protocol adapter error
TNS-00511: No listener
Linux Error: 2: No such file or directory
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=primary01)(PORT=1521)))
TNS-12541: TNS:no listener
TNS-12560: TNS:protocol adapter error
TNS-00511: No listener
Linux Error: 111: Connection refused
As you can see, the database port is 1521 without questions. But the listener is not started. So let’s start it up.
[oracle@primary01 ~]$ lsnrctl start
LSNRCTL for Linux: Version 12.1.0.1.0 - Production on 22-JUL-2014 19:23:59
Copyright (c) 1991, 2013, Oracle. All rights reserved.
Starting /u01/app/oracle/product/12.1.0/dbhome_1/bin/tnslsnr: please wait...
TNSLSNR for Linux: Version 12.1.0.1.0 - Production
System parameter file is /u01/app/oracle/product/12.1.0/dbhome_1/network/admin/listener.ora
Log messages written to /u01/app/oracle/diag/tnslsnr/primary01/listener/alert/log.xml
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=primary01)(PORT=1521)))
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 12.1.0.1.0 - Production
Start Date 22-JUL-2014 19:23:59
Uptime 0 days 0 hr. 0 min. 2 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/product/12.1.0/dbhome_1/network/admin/listener.ora
Listener Log File /u01/app/oracle/diag/tnslsnr/primary01/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=primary01)(PORT=1521)))
The listener supports no services
The command completed successfully
For more testing skills, you may check Oracle 19c Net Services Administrator’s Guide: 15 Testing Connections.
I’ve been working this issue all day, reading posts here and other locations. I’m just not able to get past this error. I can connect just fine locally on my server (CentOS), but continue to get the TNS:no listener error when trying to connect via my Mac (OSX Mavericks) which is on the same subnet. Below are some notes I’ve captured based on what information I see that has been requested for this type of issue:
--------------------------------------------------------------------------------
MISC NETWORK CONFIG:
--------------------------------------------------------------------------------
[root@rubyrailssvr ~]# more /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.1.14 rubyrailssvr.homenet.com
[root@rubyrailssvr ~]#
[root@rubyrailssvr ~]# more /etc/sysconfig/network
NETWORKING=yes
HOSTNAME=rubyrailssvr.homenet.com
[root@rubyrailssvr ~]#
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
LISTENER.ORA File:
--------------------------------------------------------------------------------
[oracle@rubyrailssvr ~]$ more /u01/app/oracle/product/11.2.0/xe/network/admin/listener.ora
# listener.ora Network Configuration File:
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = /u01/app/oracle/product/11.2.0/xe)
(PROGRAM = extproc)
)
)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC_FOR_XE))
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.14)(PORT = 1521))
)
)
DEFAULT_SERVICE_LISTENER = (XE)
[oracle@rubyrailssvr ~]$
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
TNSNAMES.ORA File:
--------------------------------------------------------------------------------
[oracle@rubyrailssvr ~]$ more /u01/app/oracle/product/11.2.0/xe/network/admin/tnsnames.ora
# tnsnames.ora Network Configuration File:
XE =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.14)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = XE)
)
)
EXTPROC_CONNECTION_DATA =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC_FOR_XE))
)
(CONNECT_DATA =
(SID = PLSExtProc)
(PRESENTATION = RO)
)
)
[oracle@rubyrailssvr ~]$
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
SQLNET.ORA File:
--------------------------------------------------------------------------------
jfhogarty@rubyrailssvr:/u01/app/oracle/product/11.2.0/xe/network/admin$ more sqlnet.ora
SQLNET.AUTHENTICATION_SERVICES= (ALL)
NAMES.DIRECTORY_PATH= (TNSNAMES,ONAMES,HOSTNAME)
jfhogarty@rubyrailssvr:/u01/app/oracle/product/11.2.0/xe/network/admin$
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
CHECK LISTENERS:
--------------------------------------------------------------------------------
[oracle@rubyrailssvr ~]$ lsnrctl
LSNRCTL for Linux: Version 11.2.0.2.0 - Production on 13-AUG-2014 17:56:21
Copyright (c) 1991, 2011, Oracle. All rights reserved.
Welcome to LSNRCTL, type "help" for information.
LSNRCTL> status
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC_FOR_XE)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.2.0 - Production
Start Date 13-AUG-2014 17:46:45
Uptime 0 days 0 hr. 9 min. 39 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Default Service XE
Listener Parameter File /u01/app/oracle/product/11.2.0/xe/network/admin/listener.ora
Listener Log File /u01/app/oracle/diag/tnslsnr/rubyrailssvr/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC_FOR_XE)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.1.14)(PORT=1521)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=rubyrailssvr.homenet.com)(PORT=8080))(Presentation=HTTP)(Session=RAW))
Services Summary...
Service "PLSExtProc" has 1 instance(s).
Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...
Service "XE" has 1 instance(s).
Instance "XE", status READY, has 1 handler(s) for this service...
Service "XEXDB" has 1 instance(s).
Instance "XE", status READY, has 1 handler(s) for this service...
The command completed successfully
LSNRCTL>
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
ON THE CLIENT:
--------------------------------------------------------------------------------
➜ ~ more /usr/local/oracle/admin/network/tnsnames.ora
rubyrailssvr =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.14)(PORT = 1521))
(CONNECT_DATA = (SERVICE_NAME = XE))
)
rubyrailssvr.homenet.com =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.14)(PORT = 1521))
(CONNECT_DATA = (SERVICE_NAME = XE))
)
➜ ~
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
TRYING TO CONNECT:
--------------------------------------------------------------------------------
➜ ~ sqlplus system@rubyrailssvr
SQL*Plus: Release 11.2.0.4.0 Production on Wed Aug 13 18:21:50 2014
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Enter password:
ERROR:
ORA-12541: TNS:no listener
Enter user-name: %
➜ ~
➜ ~ sqlplus system@rubyrailssvr.homenet.com
SQL*Plus: Release 11.2.0.4.0 Production on Wed Aug 13 18:22:17 2014
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Enter password:
ERROR:
ORA-12541: TNS:no listener
Enter user-name:
➜ ~
--------------------------------------------------------------------------------
asked Aug 13, 2014 at 22:43
First, thanks for the response. I’m working on a Mac, and the instant client doesn’t include the tnsping utility. I had tried to login, from the remote computer, and that is where I got the TNS:no listener error. Logging in on the server is fine.
I had tried the telnet test before, but as I did not have telnet installed and running on the server, that test was not helpful. However, I decided to install telnet as it can be useful in testing. While doing so, I noticed that a command I had executed at the command line to open a port to iptables was not there. So I updated that file and now everything is working.
vim /etc/sysconfig/iptables
[BEFORE:]
# Generated by iptables-save v1.4.7 on Fri Jan 31 09:19:34 2014
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [6630:522769]
-A INPUT -p tcp -m tcp --dport 80 -j ACCEPT
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -p icmp -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A FORWARD -j REJECT --reject-with icmp-host-prohibited
COMMIT
# Completed on Fri Jan 31 09:19:34 2014
[AFTER:]
# Generated by iptables-save v1.4.7 on Fri Jan 31 09:19:34 2014
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [6630:522769]
-A INPUT -p tcp -m tcp --dport 80 -j ACCEPT
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -p icmp -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT
-A INPUT -p udp -m state --state NEW --dport 23 -j ACCEPT
-A INPUT -p tcp -m state --state NEW --dport 23 -j ACCEPT
-A INPUT -p tcp --dport 1521 -j ACCEPT
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A FORWARD -j REJECT --reject-with icmp-host-prohibited
COMMIT
# Completed on Fri Jan 31 09:19:34 2014
service iptables restart
Chased my tail so much yesterday that I never thought to review the iptables file — /slap head!
Thank you,
John…
(HoGi)
answered Aug 14, 2014 at 12:56
HoGiHoGi
711 gold badge1 silver badge6 bronze badges
My sequence of steps for troubleshooting
- Is the listener resolvable?
C:\>tnsping MYDB
(Confirms: the database listener is running on serverside) - Is there a firewall issue?
C:\>telnet hostname 1521
- Can I login?
C:\>sqlplus system/pass@MYDB
orC:\>sqlplus system/pass@hostname:1521/MYDB
(Confirms: The database is open) - Finally, chances of having a successful login with your favorite dev-tool has increased by 100%
answered Aug 14, 2014 at 5:20
In listener.ora file
set HOST=LOCALHOST
reason being that if your on a wireless network you can get assigned different ip addresses after every reboot which invalidates your listener settings if using a fixed ip address in your listener.ora file.
With HOST=LOCALHOST you are guaranteed consistency with regards the ip address settings between system reboots when it comes time that the listener service starts up.
answered Nov 6, 2015 at 15:48
Its too late but I also face this problem currently and I solved this by.
- Go to Net Manager(Oracle Net Manager) in your oracle installed
system. - Expand Local > Listners > LISTNER.
- Add new address protocol:TCP/IP, Host:YOURPCNAME.DOMAIN, Port:YOUR PORT.
- Go to File > Save Network Configuration.
- RESTART system.
below is snapshot for adding new address
answered Nov 19, 2016 at 9:04
ORA-12541: TNS:no listener error occurs when the listener for the requested resource is not started or configured incorrectly. The error happens if the listener is down when it tries to connect, or if it hasn’t been started or is set incorrectly. Furthermore, it might be caused by a network connectivity issue. Follow the steps given below to determine what could be causing the issue ORA-12541: TNS:no listener.
The oracle listener is used to connect to a database by listening to it. The Oracle database listener configurations are stored in the listener.ora and tnsnames.ora files. If someone tries to connect to the database, the connection configuration is compared to the settings in the listener.ora and tnsnames.ora files. If the configurations match, the database listener is not running or not started. It’s likely that when the listener initially started listening, they made an error. The listener might also be stopped or not started. If you restart the listener, the error ORA-12541: TNS:no listener will be resolved.
The Problem
The error ORA-12541: TNS:no listener will be thrown if the database listener is not started or stopped when attempting to create a database connection. It’s possible that the sqlplus command is operating OK. The error will be thrown when you try to connect to the database. The database connection cannot be established because the listener is unavailable and not listening.
oracle@localhost ~]$ sqlplus
SQL*Plus: Release 19.0.0.0.0 - Production on Thu Apr 7 09:36:12 2022
Version 19.3.0.0.0
Copyright (c) 1982, 2019, Oracle. All rights reserved.
Enter user-name: hr
Enter password:
ERROR:
ORA-12541: TNS:no listener
Enter user-name:
Solution 1
The Oracle database will throw this error if the listener is not started or terminated. Check the database listener’s status first. The database listener’s status may be obtained with the following command. To verify the status of the database listener, use the command below from the command line.
[oracle@localhost ~]$ lsnrctl status
LSNRCTL for Linux: Version 19.0.0.0.0 - Production on 07-APR-2022 09:43:06
Copyright (c) 1991, 2019, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1)))
TNS-12541: TNS:no listener
TNS-12560: TNS:protocol adapter error
TNS-00511: No listener
Linux Error: 2: No such file or directory
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=0.0.0.0)(PORT=1521)))
TNS-12541: TNS:no listener
TNS-12560: TNS:protocol adapter error
TNS-00511: No listener
Linux Error: 111: Connection refused
[oracle@localhost ~]$
Solution 2
Stop and restart the listener if you notice any abnormalities in the state of the listener. The database will shut off the listener if it is already running. It will display that the listener is not started if it is not running. Stop and start the listener to resolve the error ORA-12541: TNS:no listener.
[oracle@localhost ~]$ lsnrctl stop
LSNRCTL for Linux: Version 19.0.0.0.0 - Production on 07-APR-2022 09:36:07
Copyright (c) 1991, 2019, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1)))
The command completed successfully
[oracle@localhost ~]$ lsnrctl start
LSNRCTL for Linux: Version 19.0.0.0.0 - Production on 07-APR-2022 09:43:35
Copyright (c) 1991, 2019, Oracle. All rights reserved.
Starting /u01/app/oracle/product/version/db_1/bin/tnslsnr: please wait...
TNSLSNR for Linux: Version 19.0.0.0.0 - Production
System parameter file is /u01/app/oracle/product/version/db_1/network/admin/listener.ora
Log messages written to /u01/app/oracle/diag/tnslsnr/localhost/listener/alert/log.xml
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1)))
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=0.0.0.0)(PORT=1521)))
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 19.0.0.0.0 - Production
Start Date 07-APR-2022 09:43:35
Uptime 0 days 0 hr. 0 min. 0 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Default Service orclcdb
Listener Parameter File /u01/app/oracle/product/version/db_1/network/admin/listener.ora
Listener Log File /u01/app/oracle/diag/tnslsnr/localhost/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=0.0.0.0)(PORT=1521)))
Services Summary...
Service "orclcdb" has 1 instance(s).
Instance "orclcdb", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
[oracle@localhost ~]$
Solution 3
If the error persists when connecting to the database, there might be a problem with the listener.ora setups. Examine the files listener.ora and tnsnames.ora. Modify the details if they differ from the values provided in the database connection string. This will resolve the error ORA-12541: TNS:no listener . The improper setting in the listener.ora and tnsnames.ora files will cause the database listener to fail to start. Ensure that all of the parameters are valid and that the database listener starts without problem.