R3166-R3206-HP High-End Firewalls Network Management Configuration Guide-6PW101

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Figure 80 DNS proxy networking application
Operation of a DNS proxy
1. A DNS client considers the DNS proxy as the DNS server, and sends a DNS request to the DNS
proxy. The destination address of the request is the IP address of the DNS proxy.
2. The DNS proxy searches the local static domain name resolution table after receiving the request.
If the requested information exists in the table, the DNS proxy returns a DNS reply to the client.
3. If the requested information does not exist in the static domain name resolution table, the DNS
proxy sends the request to the designated DNS server for domain name resolution.
4. After receiving a reply from the DNS server, the DNS proxy forwards the reply to the DNS client.
Configuring DNS in the web interface
Configuration overview
DNS provides three functions, static name resolution, dynamic domain name resolution, and DNS proxy.
• Static name resolution: Name resolution is carried out through manually configured name
resolution entries.
• Dynamic name resolution: The firewall resolves domain names through the DNS server.
• DNS proxy: You can configure a device as a DNS proxy.
NOTE:
If both static domain name resolution and dynamic domain name resolution are configured, the firewall
first checks the static name resolution table for an IP address. If no IP address is available, it then contacts
the DNS server for dynamic name resolution.
Configuring static name resolution table
Perform the tasks in Table 30 to configure static name resolution table.