ORA-17002: io exception: the network adaptor could not establish the connection Vendor code 17002

I got ” ORA-17002: io exception: the network adaptor could not establish the connection Vendor code 17002″  error in Oracle database.

ORA-17002: io exception: the network adaptor could not establish the connection Vendor code 17002

Details of error are as follows.

ORA-17002: io exception: the network adaptor could not establish the connection Vendor code 17002

 io exception: the network adaptor could not establish the connection Vendor code 17002

This ORA-17002 error is related with the ORA-12541: TNS:no listener error.

This error is related with the listener of database server, if you got this error, then check your database listener as follows.

$ lsnrctl status listener

Listener should be always started.

You can stop and start the Listener as follows.

$  srvctl start listener

$ srvctl stop listener

or

$ lsnrctl stop listener

$ lsnrctl start listener

Edit the server side sqlnet.ora file and add this parameter:

SQLNET.INBOUND_CONNECT_TIMEOUT=240

There is no need to restart either the listener or the database after this change unless the database is running in shared server mode.
The next dedicated server process that gets spawned will pick up the new setting.

Do you want to learn Oracle Database for Beginners, then read the following articles.

Oracle Tutorial | Oracle Database Tutorials for Beginners ( Junior Oracle DBA )