Originally posted by akhadar
Instead of strugling further follow the steps.

1.Alter database rename global_names to xxx
on both the servers.
2.create database link abcd.xxx connect to user_name identified by password using
'(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = your host )(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = database_sid)
)
)';
It was really my bad akhadar,
Though I mention earlier that without touching global_names, the preceeding post that i have made is for prasen999 to understand what is the usual oracle behaviour for db link creation when global_names is not used.

prasen999,
You are close, it will also help you if you just read documents for proper and easier understanding.