An enterprise deploys Network Secure as a gateway to enable the DNS proxy function. For security purposes, you need to disable the permission of port 53 of accessing the DNS service in the WAN zone.

Step 1.Click Add. Then, the Add Local ACL Policy dialog box appears.

Name: Enter Deny_WAN_DNS.
Source:

Network Object: Select All.

Src Zone: Select WAN.
Services:

Services: Select built-in related DNS services.

Action: Select Deny.

Step 2.Click Save. Then, the configuration is complete.

Step 3.PCs in the LAN segment can use Network Secure to perform DNS resolution. After the WAN IP address telnet test, it is verified that port 53 for Network Secure's WAN interface DNS service is not available.