Oracle Listener cannot be started

How to Solve the Oracle Listener cannot be started .Following below steps to make start the listener.

Symptom:

When you try to do it manually, it throws the error below:

:adm $ lsnrctl start [LISTENER_NAME]

LSNRCTL for : Version 12.1.0.2.0 - Production on 30-AUG-2012 18:06:43

Starting /oracle//121/bin/tnslsnr: please wait...

TNSLSNR for : Version 12.1.0.2.0 - Production

System parameter file is /oracle//121/network/admin/listener.ora

Log messages written to /oracle//121/network/log/listener.log

Error listening on: (ADDRESS=(PROTOCOL=IPC)(KEY=.WORLD))

TNS-12555: TNS:permission denied

TNS-12560: TNS:protocol adapter error

  TNS-00525: Insufficient privilege for operation

    Error: 1: Not owner

Solution:

Make sure that both adm and oracle/ora have full permissions in the following two directories:

• /tmp/.oracle
• /var/tmp/.oracle

Correct by either changing the ownership or granting more privileges:

• chown ora.dba /tmp/.oracle
• chmod 774 /tmp/.oracle