Oracle Local database Link slow resolution

1. The Oracle connection is slow during the test:
conn = env->createconnection (user, passwd, connect_string);
Stepping here, waiting for the return to be slow.
Processing method:
1, detection phenomenon problems:
1) sqlplus [email protected] Database username/password
Return prompt, very slow.
2) tnsping oralce server IP, the speed is also very slow.
Solve the problem:
There is a problem with DNS configuration, if you do not use DNS, the/etc/resolv.conf inside the log off or delete this file.

Borrowing: http://www.itpub.net/thread-1418833-1-1.html

Oracle Local database Link slow resolution