ERROR: ORA-21561: OID generation failed Error While connecting to an Database from a client.

Problem:
  
 $sqlplus testing/testing@racdb

SQL*Plus: Release 11.2.0.3.0 Production on Fri Jan 3 17:29:55 2014

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ERROR:
ORA-21561: OID generation failed

Enter user-name:
ERROR:
ORA-01017: invalid username/password; logon denied

Enter user-name:
ERROR:
ORA-01017: invalid username/password; logon denied


SP2-0157: unable to CONNECT to ORACLE after 3 attempts, exiting SQL*Plus
============================================
Solution:
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This problem is due to wrong entry in host file
So the entry should be like this

127.0.0.1 loopback localhost
192.168.1.10 myhost.mydomain.com myhost


Hope U guys can get the solution.