Tns: connection timeout error

While connecting SQL*PLUS from windows or any linux machine to the database server hosted on some other machine sometimes this connection timeout error comes.

Solution:

1) Check your listener is working fine on the database server with command like LSNRCTL STATUS

2) TNSPING serverIP or ORACLE SID of hosted database server from windows machine command prompt. The status will show Ok. It means you are able to tnsping to database server.

3) TNSNAMES.ora file should be having the correct connect identifier specified on both the windows and hosted database server.
The path generally on windows is D:\app\oracle\product\11.2.0\db_1\network\admin\tnsnames.ora
The path generally on Linux is u01\oracle\product\11.2.0\db_1\network\admin\tnsnames.ora