Listener start is failing with TNS-12560: TNS:protocol adapter error

Hi There,
  Recently we got an interesting problem while starting DB listener.

$ lsnrctl status qat

LSNRCTL for Linux: Version 11.2.0.3.0 - Production on 30-DEC-2013 19:39:15

Copyright (c) 1991, 2011, Oracle.  All rights reserved.

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=myhost.mydomain.com)(PORT=1522)))
TNS-12541: TNS:no listener
 TNS-12560: TNS:protocol adapter error
  TNS-00511: No listener
   Linux Error: 111: Connection refused
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1522)))
TNS-12541: TNS:no listener
 TNS-12560: TNS:protocol adapter error
  TNS-00511: No listener
   Linux Error: 111: Connection refused





Solution:
  Check the hostfile entry it should be like this

127.0.0.1 loopback localhost
192.168.1.10 myhost.mydomain.com myhost

Hope you will get your solution..