Dns Proxy; Ddns Client - Siemens SIMATIC NET SCALANCE SC-600 Configuration Manual

Configuring with Web Based Management
4.4 "System" menu
• DNS Server Address
Shows the IP address of the DNS server.
• Origin
Shows whether the DNS server was configured manually or was assigned by DHCP.
4.4.3.2

DNS proxy

The device provides a DNS server for the local network. If you enter the IP address of the
device in the local application as a DNS server, then the device answers the DNS
requests from its cache.
If the device does not know the IP address for a domain address, it forwards the query to
an external DNS server. How long the device keeps a domain address in the cache
depends on the host being addressed. In addition to the IP address, a DNS request to an
external DNS server also supplies the life span of this information.
Description
The page contains the following boxes:
• Enable DNS Proxy
Enable or disable the proxy of the DNS server.
• Cache Name Errors (NXDOMAIN)
Enable or disable the caching of NXDOMAIN replies. If you enable the option, the
domain names that were unknown to the DNS server remain in the cache.
4.4.3.3

DDNS client

The DDNS (Dynamic Domain Name System) is an Internet service that allows a fixed
hostname to be set up as a pseudonym for a dynamically changing IP address.
The DDNS client synchronizes the assigned IP address with the hostname registered at
the DDNS provider. This means that the device can always be reached using the same
hostname.
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SCALANCE SC-600 Web Based Management (WBM)
Configuration Manual, 10/2021, C79000-G8976-C475-03