I know what's the problem~~
i need to disable firewalld
I have installed a oracle developer on win7
and I have an oracle database 12c
when I connect from developer it said failed.
and I have check the listener is on
And I can also ping successfully from win7 machine . Any more hints??
Your listener is configured to listen on 'localhost'. And the 'ping' command just verifies that the other machine (not the DB) can be reached.
The TNSPING command will tell you if the database can be reached.