Starting TNS Listener or LSNRCTL TNS-12541, Linux Error: 111: Connection Refused

Symptoms:  Starting TNS Listener or LSNRCTL TNS-12541, Linux Error: 111: Connection Refused


Cause: You try to start the Oracle Listener and gets the error such as this:

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC)))
TNS-12541: TNS:no listener
 TNS-12560: TNS:protocol adapter error
  TNS-00511: No listener
   Linux Error: 111: Connection refused


There is possibly an incorrect IP Address specified for the host in the /etc/hosts file.
Also, the localhost reference may be incorrect or missing from the /etc/hosts file.
Oracle may not have read access to /etc/nsswitch.conf file.


Solution: Correct or make sure the mapping in the /etc/hosts file is ok (ex: 192.168.1.10     dbserver1.domain.com     dbserver).

Check that the localhost loopback name and address are correct (both long and short host names).
Ex:
127.0.0.1     localhost.localdomain    localhost

Check permissions on /etc/nsswitch.conf file to ensure group and other have read access.
If necessary change permisions on /etc/nsswitch.conf as follows:
chmod 644 /etc/nsswitch.conf


keywords:  TNS-12560, TNS-12537, TNS-00507, lsnrctl,
Doc ID 343295.1