I have this error on my r11 instance

While i try to start my lsnr i have below errors:

[oraprod@oracle]$ lsnrctl start PROD

TNS-12541: TNS:no listener
TNS-12560: TNS:protocol adapter error
TNS-00511: No listener
Linux Error: 111: Connection refused

I noticed that i have missing entery on my /etc/hosts file as:       localhost.localdomain   localhost

After add this line than i can start stop my lsnr wihtout problem

For this error please also check below note:

Starting 10gr2 TNS Listener Yields TNS-12541, Linux Error: 111: Connection Refused [ID343295.1]