Not able to start listener
LSNRCTL> status
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
TNS-12541: TNS:no listener
TNS-12560: TNS:protocol adapter error
TNS-00511: No listener
Linux Error: 111: Connection refused
LSNRCTL> start
Starting /u01/app/oracle/product/11.2.0.3/dbhome_1/bin/tnslsnr: please wait...
TNSLSNR for Linux: Version 11.2.0.3.0 - Production
Log messages written to /u01/app/oracle/diag/tnslsnr/hostname/listener/alert/log.xml
Error listening on: (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
TNS-12542: TNS:address already in use
TNS-12560: TNS:protocol adapter error
TNS-00512: Address already in use