Oracle modifies the listening port number 1521, oracle1521
In oracle, the default listening port number is 1521. Once someone scans this port number, it will know that this server is an oracle database server. This poses an extremely high security risk, how to modify the default port number of oracle to 9999:
1. view the listener status
$ Lsnrctl status
2. Stop listening
$ Lsnrctl stop
3. modify the configuration file
$ Vi $ ORACLE_HOME/network/admin/listener. ora
1521 -----> 9999
4. log on to and view the local_listener parameters.
$ Sqlplus/as sysdba
> Show parameter local_listener
(The VALUE of VALUE should be empty at this time)
5. Modify the local_listener parameter.
> Alter system set local_listener = "(address = (protocol = tcp) (host = 192.168.100.201) (port = 9999 ))";
# Host name or IP address added after the host
6. view the local_listener parameters.
> Show parameter local_listener
7. Start the listener
$ Lsnrctl start
8. view the status
$ Netstat-an | grep 9999
$ Lsnrctl status
9. Open firewall ports
$ Su-root
#/Sbin/iptables-I INPUT-p tcp -- dport 9999-j ACCEPT
#/Etc/rc. d/init. d/iptables save
The oracle listening port number has changed from 1521 to 9999.