This topic provides a firewall-based method to block external access to the Controller MySQL Database by dropping all traffic trying to connect to port 3388.
Linux such as RHEL, Centos, systems using iptables if your system uses iptables, you can do this. If not, contact your sysadmin for an alternative.
As root, these commands:
iptables -A INPUT -s 127.0.0.1 -p tcp --dport 3388 -j ACCEPT
iptables -A INPUT -p tcp --dport 3388 -j DROP
service iptables save
These commands do the following:
1. Create a firewall rule allowing port 3388 to be accessed from localhost (127.0.0.1).
2. Create a firewall rule blocking all access to port 3388.
3. Save the firewall rules so they are automatically applied at boot time.