Hi,

I have server cent os. I have to open port 443 for monitoring server. Monitoring server in cloud and managed by different vendor.

In my server I have multiple interfaces eth0, eth1, eth2.

eth0 is dedicated for monitoring.

eth1 and eth2 are data traffic interfaces.

There is very confidential data are exist in server. Is there way i can secure them.

Below is the setup. I am planning to open port https


systemctl enable firewalld
systemctl restart firewalld

firewall-cmd --zone=public --permanent --add-service=https
/etc/sysconfig/network-scripts/ifcfg-eth0

# Add
ZONE=public

systemctl restart network
systemctl restart firewalld

What are they monitoring on port 443 and how? Most devices are monitored using SNMP. Sorry I don't know firewalld so I cannot help you there. I don't think opening 443 to the public is a good idea unless you are running a web site. And if your vendor is monitoring your server over 443 then anyone else could do the same. You might want to also lock this down to just the vendor.

if ping is blocked, nagios and other tool can use a tcp port to check the status of the server (up/down) .. could this be the case? but it could be any port not just https.

they may be monitoring the status of a https web service that is using port 443.. if that is the case the webserver must be listening on eth0
i do not think you can have a https service open without a webserver.

to secure your setup you can setup the firewall to only accept connections from certain IP your monitoring provider must provide you with their public ip addresses. if theres a web service behind such as a login prompt, you can set up fail2ban and ban ip that try brute force attacks.. say ban an ip if connects 5 times in the last x minutes and whitelist your providers ip addresses as monitoring tools tends to connect every 5 minutes to check the status of the service they are monitoring.