Sample tnsnames.ora file for Linux

Oracle Version: oracle 11g
Oracle SID: orcl
OS Version:- RHEL 6
Hostname:- server1.example.com
Server IP: 192.168.72.120


$ vi $ORACLE_HOME/network/admin/tnsnames.ora
# tnsnames.ora Network Configuration File: /i01/app/oracle/product/11.2.0/db_1/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.
orcl =
  (DESCRIPTION =
         (ADDRESS = (PROTOCOL = TCP)(HOST = server1.example.com)(PORT = 1521))
         (CONNECT_DATA =
           (SERVER = DEDICATED)
    (SERVICE_NAME = orcl)
    )
  )