The MX Security Appliance responds to ICMP ping by default but can be configured to reply to specific IP addresses or none at all.
1. Log on to your Dashboard and navigate to Configure > Firewall.
2. In the section labeled Appliance services, you will see the option ICMP Ping.
3. The text box for this option allows you to specify remote access rules for the local status page. The below options can be used:
a) Any - The MX will reply to all pings from external IP addresses. This is not a recommended setting since it opens your network to anyone on the Internet.
b) None - The MX will not reply to pings from any external IP addresses.
c) Allowed remote IPs - The remote IP address(s) written in CIDR notation you would like to give remote access to. A comma separated list of IP addresses can be entered if specifying multiple subnets. See Fig 1 below.
Figure 1. Any external ICMP requests to the WAN IP of the MX will be matched to this table. If there is no match the MX will not respond to the sender.