1521 포트 허용정책 추가하기
# vi /etc/sysconfig/iptables
-A INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 1521 -j ACCEPT
-A INPUT -j REJECT --reject-with icmp-host-prohibited
# service iptables restart