I have Oracle 12c db on first virtual machine and Client on second. How to connect them? And how to check the connection?
machines: Linux RedHat 6
Here's an example TNSNAMES.ORA from one of our servers:
PRODDB = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = WIN-ORACLE-EN-1)(PORT = 1521)) ) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = PRODDB) ) )
You also need to make sure that the LISTENER.ORA has been configured correctly and that both database and listener services are running.
After installing SQL*plus or SQL Developer, also make sure that on the client machine the TNSNAMES.ORA matches the server configuration, then try:
and you should receive an "OK" as a result.
Here's an article with more information (taken from "dummies.com", shouldn't be any insult ;-) ):